Misplaced Pages

#693306

107-728: A smartphone , often simply called a phone , is a mobile device that combines the functionality of a traditional mobile phone with advanced computing capabilities. It typically has a touchscreen interface, allowing users to access a wide range of applications and services, such as web browsing , email , and social media , as well as multimedia playback and streaming . Smartphones have built-in cameras , GPS navigation , and support for various communication methods, including voice calls, text messaging , and internet-based messaging apps. Smartphones are distinguished from older-design feature phones by their more advanced hardware capabilities and extensive mobile operating systems , access to

214-530: A Sharp J-Phone model sold in Japan in November 2000. It could instantly transmit pictures via cell phone telecommunication . By the mid-2000s, higher-end cell phones commonly had integrated digital cameras. In 2003 camera phones outsold stand-alone digital cameras, and in 2006 they outsold film and digital stand-alone cameras. Five billion camera phones were sold in five years, and by 2007 more than half of

321-429: A depletion layer by forcing the positively charged holes away from the gate-insulator/semiconductor interface, leaving exposed a carrier-free region of immobile, negatively charged acceptor ions (see doping ). If V G is high enough, a high concentration of negative charge carriers forms in an inversion layer located in a thin layer next to the interface between the semiconductor and the insulator. Conventionally,

428-411: A gyroscope , an accelerometer , and more ), and support diverse wireless communication protocols (such as LTE , 5G NR , Wi-Fi , Bluetooth , and satellite navigation ). In the mid-2020s, smartphone manufacturers have begun to integrate satellite messaging connectivity and satellite emergency services into devices for use in remote regions where there is no reliable cellular network . Following

535-426: A software update that gave the iPhone a built-in on-device App Store allowing direct wireless downloads of third-party software. This kind of centralized App Store and free developer tools quickly became the new main paradigm for all smartphone platforms for software development , distribution , discovery, installation , and payment, in place of expensive developer tools that required official approval to use and

642-692: A " keyboard bar " form factor, like the BlackBerry line, Windows Mobile smartphones, Palm Treos , and some of the Nokia Eseries . A few hid their full physical QWERTY keyboard in a sliding form factor , like the Danger Hiptop line. Some even had only a numeric keypad using T9 text input , like the Nokia Nseries and other models in the Nokia Eseries . Resistive touchscreens with stylus -based interfaces could still be found on

749-560: A "devices and services" company. Despite the growth of Windows Phone and the Lumia range (which accounted for nearly 90% of all Windows Phone devices sold), the platform never had significant market share in the key U.S. market, and Microsoft was unable to maintain Windows Phone's momentum in the years that followed, resulting in dwindling interest from users and app developers. After Balmer was succeeded by Satya Nadella (who has placed

856-564: A MOSFET. In the case of a p-type MOSFET, bulk inversion happens when the intrinsic energy level at the surface becomes smaller than the Fermi level at the surface. This can be seen on a band diagram. The Fermi level defines the type of semiconductor in discussion. If the Fermi level is equal to the Intrinsic level, the semiconductor is of intrinsic, or pure type. If the Fermi level lies closer to

963-586: A bag or pocket but can easily be misplaced. Hence, mobile hosts with embedded devices such as an autonomous vehicle can appear larger than pocket-sized. The most common size of a mobile computing device is pocket-sized, but other sizes for mobile devices exist. Mark Weiser , known as the father of ubiquitous computing , referred to device sizes that are tab-sized, pad, and board sized, where tabs are defined as accompanied or wearable centimeter-sized devices, e.g. smartphones , phablets and tablets are defined as hand-held decimeter-sized devices. If one changes

1070-535: A bipolar transistor. The subthreshold I–V curve depends exponentially upon threshold voltage, introducing a strong dependence on any manufacturing variation that affects threshold voltage; for example: variations in oxide thickness, junction depth, or body doping that change the degree of drain-induced barrier lowering. The resulting sensitivity to fabricational variations complicates optimization for leakage and performance. When V GS > V th and V DS < V GS  − V th : The transistor

1177-404: A buried oxide is formed below a thin semiconductor layer. If the channel region between the gate dielectric and the buried oxide region is very thin, the channel is referred to as an ultrathin channel region with the source and drain regions formed on either side in or above the thin semiconductor layer. Other semiconductor materials may be employed. When the source and drain regions are formed above

SECTION 10

#1732776729694

1284-438: A dependence on third-party sources providing applications for multiple platforms. The advantages of a design with software powerful enough to support advanced applications and a large capacitive touchscreen affected the development of another smartphone OS platform, Android , with a more BlackBerry-like prototype device scrapped in favor of a touchscreen device with a slide-out physical keyboard, as Google's engineers thought at

1391-404: A dual five-megapixel rear camera setup for spatial imaging, among the earliest mobile phones with more than one rear camera . The 2012 Samsung Galaxy S3 introduced the ability to capture photos using voice commands . Mobile device Device mobility can be viewed in the context of several qualities: Strictly speaking, many so-called mobile devices are not mobile. It is the host that

1498-487: A few smartphones, like the Palm Treos , which had dropped their handwriting input after a few early models that were available in versions with Graffiti instead of a keyboard. The late 2000s and early 2010s saw a shift in smartphone interfaces away from devices with physical keyboards and keypads to ones with large finger-operated capacitive touchscreens. The first phone of any kind with a large capacitive touchscreen

1605-419: A handheld supplement to bulkier laptops . During the same period, the mobile phone evolved from supporting voice communication only to accommodating text messaging , Internet connectivity, multimedia, and videotelephony . These feature phones eventually gave way to the modern smartphone , which combined all the aforementioned devices, and more, into one device. Since the late 2000s, smartphones have been

1712-403: A large capacitive touchscreen as the sole means of interaction, and led to the decline of earlier, keyboard- and keypad-focused platforms. Later, navigation keys such as the home , back , menu , task and search buttons have also been increasingly replaced by nonphysical touch keys, then virtual, simulated on-screen navigation keys, commonly with access combinations such as a long press of

1819-714: A larger focus on software and cloud computing) as CEO of Microsoft, it took a $ 7.6 billion write-off on the Nokia assets in July 2015, and laid off nearly the entire Microsoft Mobile unit in May 2016. Prior to the completion of the sale to Microsoft, Nokia released a series of Android-derived smartphones for emerging markets known as Nokia X , which combined an Android-based platform with elements of Windows Phone and Nokia's feature phone platform Asha , using Microsoft and Nokia services rather than Google. The first commercial camera phone

1926-454: A lesser extent, handheld video game consoles , e-reader devices, pocket calculators , and GPS tracking units . Since the early 2010s, improved hardware and faster wireless communication (due to standards such as LTE and later 5G NR) have bolstered the growth of the smartphone industry . As of 2014, over a billion smartphones are sold globally every year. In 2019 alone, 1.54 billion smartphone units were shipped worldwide. 75.05 percent of

2033-476: A long-channel device, there is no drain voltage dependence of the current once V DS ≫ V T {\displaystyle V_{\text{DS}}\gg V_{\text{T}}} , but as channel length is reduced drain-induced barrier lowering introduces drain voltage dependence that depends in a complex way upon the device geometry (for example, the channel doping, the junction doping and so on). Frequently, threshold voltage V th for this mode

2140-746: A major partnership with Microsoft, under which it would exclusively use Windows Phone on all of its future smartphones, and integrate Microsoft's Bing search engine and Bing Maps (which, as part of the partnership, would also license Nokia Maps data) into all future devices. The announcement led to the abandonment of both Symbian, as well as MeeGo —a Linux-based mobile platform it was co-developing with Intel. Nokia's low-end Lumia 520 saw strong demand and helped Windows Phone gain niche popularity in some markets, overtaking BlackBerry in global market share in 2013. In mid-June 2012, Meizu released its mobile operating system, Flyme OS . Many of these attempts to compete with Android and iPhone were short-lived. Over

2247-410: A memory chip or microprocessor. Since MOSFETs can be made with either p-type or n-type semiconductors, complementary pairs of MOS transistors can be used to make switching circuits with very low power consumption, in the form of CMOS logic . The basic principle of the field-effect transistor was first patented by Julius Edgar Lilienfeld in 1925. In 1934, inventor Oskar Heil independently patented

SECTION 20

#1732776729694

2354-528: A redesigned user interface, support for gestures such as pinch-to-zoom, and a new web browser based on the same WebKit rendering engine used by the iPhone. The following year, RIM released BlackBerry OS 7 and new models in the Bold and Torch ranges, which included a new Bold with a touchscreen alongside its keyboard, and the Torch 9860—the first BlackBerry phone to not include a physical keyboard. In 2013, it replaced

2461-414: A rotary knob ring around the lens and a tripod mount. While screen sizes have increased, manufacturers have attempted to make smartphones thinner at the expense of utility and sturdiness, since a thinner frame is more vulnerable to bending and has less space for components, namely battery capacity. The iPhone and later touchscreen-only Android devices together popularized the slate form factor , based on

2568-480: A silicon MOS transistor in 1959 and successfully demonstrated a working MOS device with their Bell Labs team in 1960. Their team included E. E. LaBate and E. I. Povilonis who fabricated the device; M. O. Thurston, L. A. D’Asaro, and J. R. Ligenza who developed the diffusion processes, and H. K. Gummel and R. Lindner who characterized the device. This was a culmination of decades of field-effect research that began with Lilienfeld. The first MOS transistor at Bell Labs

2675-511: A similar device in Europe. In the 1940s, Bell Labs scientists William Shockley , John Bardeen and Walter Houser Brattain attempted to build a field-effect device, which led to their discovery of the transistor effect. However, the structure failed to show the anticipated effects, due to the problem of surface states : traps on the semiconductor surface that hold electrons immobile. With no surface passivation , they were only able to build

2782-413: Is a type of field-effect transistor (FET), most commonly fabricated by the controlled oxidation of silicon . It has an insulated gate, the voltage of which determines the conductivity of the device. This ability to change conductivity with the amount of applied voltage can be used for amplifying or switching electronic signals . The term metal–insulator–semiconductor field-effect transistor ( MISFET )

2889-748: Is a weak-inversion current, sometimes called subthreshold leakage. In weak inversion where the source is tied to bulk, the current varies exponentially with V GS {\displaystyle V_{\text{GS}}} as given approximately by: I D ≈ I D0 e V GS − V th n V T , {\displaystyle I_{\text{D}}\approx I_{\text{D0}}e^{\frac {V_{\text{GS}}-V_{\text{th}}}{nV_{\text{T}}}},} where I D0 {\displaystyle I_{\text{D0}}} = current at V GS = V th {\displaystyle V_{\text{GS}}=V_{\text{th}}} ,

2996-437: Is almost synonymous with MOSFET . Another near-synonym is insulated-gate field-effect transistor ( IGFET ). The main advantage of a MOSFET is that it requires almost no input current to control the load current, when compared to bipolar junction transistors (BJTs). In an enhancement mode MOSFET, voltage applied to the gate terminal increases the conductivity of the device. In depletion mode transistors, voltage applied at

3103-454: Is also a prospect of leveraging mobile devices to facilitate cross-border services, warranting regulatory attention. Within the military domain, mobile devices have introduced novel prospects for delivering training and educational resources to soldiers, irrespective of their stationed location. MOSFET scaling In electronics , the metal–oxide–semiconductor field-effect transistor ( MOSFET , MOS-FET , MOS FET , or MOS transistor )

3210-714: Is defined as the gate voltage at which a selected value of current I D0 occurs, for example, I D0 = 1   μA, which may not be the same V th -value used in the equations for the following modes. Some micropower analog circuits are designed to take advantage of subthreshold conduction. By working in the weak-inversion region, the MOSFETs in these circuits deliver the highest possible transconductance-to-current ratio, namely: g m / I D = 1 / ( n V T ) {\displaystyle g_{m}/I_{\text{D}}=1/\left(nV_{\text{T}}\right)} , almost that of

3317-415: Is equivalent to a planar capacitor , with one of the electrodes replaced by a semiconductor. When a voltage is applied across a MOS structure, it modifies the distribution of charges in the semiconductor. If we consider a p-type semiconductor (with N A the density of acceptors , p the density of holes; p = N A in neutral bulk), a positive voltage, V G , from gate to body (see figure) creates

Smartphone - Misplaced Pages Continue

3424-425: Is mobile, i.e., a mobile human host carries a non-mobile smartphone device. An example of a true mobile computing device, where the device itself is mobile, is a robot . Another example is an autonomous vehicle . There are three basic ways mobile devices can be physically bound to mobile hosts: Accompanied refers to an object being loosely bound and accompanying a mobile host, e.g., a smartphone can be carried in

3531-466: Is often regarded as synonymous with having wireless connectivity, these terms are different. Not all network access by mobile users, applications, and devices needs to be via wireless networks and vice versa. Wireless access devices can be static and mobile users can move between wired and wireless hotspots such as in Internet cafés. Some mobile devices can be used as mobile Internet devices to access

3638-501: Is the charge-carrier effective mobility, W {\displaystyle W} is the gate width, L {\displaystyle L} is the gate length and C ox {\displaystyle C_{\text{ox}}} is the gate oxide capacitance per unit area. The transition from the exponential subthreshold region to the triode region is not as sharp as the equations suggest. When V GS > V th and V DS ≥ (V GS  – V th ): The switch

3745-787: Is turned on, and a channel has been created which allows current between the drain and the source. The MOSFET operates like a resistor, controlled by the gate voltage relative to both the source and drain voltages. The current from drain to source is modeled as: I D = μ n C ox W L ( ( V GS − V t h ) V DS − V DS 2 2 ) {\displaystyle I_{\text{D}}=\mu _{n}C_{\text{ox}}{\frac {W}{L}}\left(\left(V_{\text{GS}}-V_{\rm {th}}\right)V_{\text{DS}}-{\frac {{V_{\text{DS}}}^{2}}{2}}\right)} where μ n {\displaystyle \mu _{n}}

3852-427: Is turned on, and a channel has been created, which allows current between the drain and source. Since the drain voltage is higher than the source voltage, the electrons spread out, and conduction is not through a narrow channel but through a broader, two- or three-dimensional current distribution extending away from the interface and deeper in the substrate. The onset of this region is also known as pinch-off to indicate

3959-447: The 45 nanometer node. When a voltage is applied between the gate and the source, the electric field generated penetrates through the oxide and creates an inversion layer or channel at the semiconductor-insulator interface. The inversion layer provides a channel through which current can pass between source and drain terminals. Varying the voltage between the gate and body modulates the conductivity of this layer and thereby controls

4066-455: The BJT and thyristor transistors. In 1955, Carl Frosch and Lincoln Derick accidentally grew a layer of silicon dioxide over the silicon wafer, for which they observed surface passivation effects. By 1957 Frosch and Derick, using masking and predeposition, were able to manufacture silicon dioxide field effect transistors; the first planar transistors, in which drain and source were adjacent at

4173-1031: The Japanese market , such as mobile payments and shopping, near-field communication (NFC) allowing mobile wallet functionality to replace smart cards for transit fares, loyalty cards, identity cards, event tickets, coupons, money transfer, etc., downloadable content like musical ringtones , games , and comics , and 1seg mobile television . Phones built by Japanese manufacturers used custom firmware , however, and did not yet feature standardized mobile operating systems designed to cater to third-party application development , so their software and ecosystems were akin to very advanced feature phones . As with other feature phones, additional software and services required partnerships and deals with providers. The degree of integration between phones and carriers, unique phone features, non-standardized platforms, and tailoring to Japanese culture made it difficult for Japanese manufacturers to export their phones, especially when demand

4280-589: The Nokia 9000 Communicator , a digital cellular PDA based on the Nokia 2110 with an integrated system based on the PEN/GEOS 3.0 operating system from Geoworks . The two components were attached by a hinge in what became known as a clamshell design , with the display above and a physical QWERTY keyboard below. The PDA provided e-mail ; calendar, address book, calculator and notebook applications; text-based Web browsing; and could send and receive faxes. When closed,

4387-562: The Nokia N8 , Sony Ericsson Satio , and Samsung M8910 Pixon12 feature phone had 12 MP. The main camera of the 2009 Nokia N86 uniquely features a three-level aperture lens. The Altek Leo, a 14-megapixel smartphone with 3x optical zoom lens and 720p HD video camera was released in late 2010. In 2011, the same year the Nintendo 3DS was released, HTC unveiled the Evo 3D , a 3D phone with

Smartphone - Misplaced Pages Continue

4494-555: The OmniGo 700LX , a modified HP 200LX palmtop PC with a Nokia 2110 mobile phone piggybacked onto it and ROM -based software to support it. It had a 640 × 200 resolution CGA compatible four-shade gray-scale LCD screen and could be used to place and receive calls, and to create and receive text messages, emails and faxes. It was also 100% DOS 5.0 compatible, allowing it to run thousands of existing software titles, including early versions of Windows . In August 1996, Nokia released

4601-562: The Pre 3 and HP TouchPad tablet. As part of a proposed divestment of its consumer business to focus on enterprise software, HP abruptly ended development of future webOS devices in August 2011, and sold the rights to webOS to LG Electronics in 2013, for use as a smart TV platform. Research in Motion introduced the vertical-sliding BlackBerry Torch and BlackBerry OS 6 in 2010, which featured

4708-627: The exponential scaling and miniaturization of MOS transistors down to sub-micron levels ( Moore's law ), the improved lithium-ion battery , faster digital mobile data networks ( Edholm's law ), and more mature software platforms that allowed mobile device ecosystems to develop independently of data providers . In the 2000s, NTT DoCoMo 's i-mode platform, BlackBerry , Nokia 's Symbian platform, and Windows Mobile began to gain market traction, with models often featuring QWERTY keyboards or resistive touchscreen input and emphasizing access to push email and wireless internet . In

4815-477: The installed base of all mobile phones were camera phones. Sales of separate cameras peaked in 2008. Many early smartphones did not have cameras at all, and earlier models that had them had low performance and insufficient image and video quality that could not compete with budget pocket cameras and fulfill user's needs. By the beginning of the 2010s almost all smartphones had an integrated digital camera. The decline in sales of stand-alone cameras accelerated due to

4922-413: The internet , business applications, mobile payments , and multimedia functionality, including music, video, gaming , radio , and television . Smartphones typically contain a number of metal–oxide–semiconductor (MOS) integrated circuit (IC) chips, include various sensors that can be leveraged by pre-installed and third-party software (such as a magnetometer , a proximity sensor , a barometer ,

5029-477: The " Pocket PC " versions of what was later Windows Mobile , and the UIQ interface that was originally designed for pen-based PDAs on Symbian OS devices resulted in some early smartphones having stylus-based interfaces. These allowed for virtual keyboards and handwriting input, thus also allowing easy entry of Asian characters. By the mid-2000s, the majority of smartphones had a physical QWERTY keyboard. Most used

5136-705: The "smartphones" in this era were hybrid devices that combined these existing familiar PDA OSes with basic phone hardware. The results were devices that were bulkier than either dedicated mobile phones or PDAs, but allowed a limited amount of cellular Internet access. PDA and mobile phone manufacturers competed in reducing the size of devices. The bulk of these smartphones combined with their high cost and expensive data plans, plus other drawbacks such as expansion limitations and decreased battery life compared to separate standalone devices, generally limited their popularity to " early adopters " and business users who needed portable connectivity. In March 1996, Hewlett-Packard released

5243-441: The 21st-century, mobile phone providers began making television available on cellular phones. In the 2010s, mobile devices were observed to frequently include the ability to sync and share a variety of data despite the distance or specifications of the devices. In the medical field, mobile devices are quickly becoming essential tools for accessing clinical information such as drugs, treatment, and even medical calculations. Due to

5350-432: The Fermi level and when the voltage reaches the threshold voltage, the intrinsic level does cross the Fermi level, and that is what is known as inversion. At that point, the surface of the semiconductor is inverted from p-type into n-type. If the Fermi level lies above the intrinsic level, the semiconductor is of n-type, therefore at inversion, when the intrinsic level reaches and crosses the Fermi level (which lies closer to

5457-558: The Internet while moving, but they do not need to do this and many phone functions or applications are still operational even while disconnected from the Internet . What makes the mobile device unique compared to other technologies is the inherent flexibility in the hardware and software. Flexible applications include video chat, web browsing, payment systems, near field communication, audio recording etc. As mobile devices become ubiquitous, there will be an increase of services which include

SECTION 50

#1732776729694

5564-463: The addition of n-type source and drain regions. The MOS capacitor structure is the heart of the MOSFET. Consider a MOS capacitor where the silicon base is of p-type. If a positive voltage is applied at the gate, holes which are at the surface of the p-type substrate will be repelled by the electric field generated by the voltage applied. At first, the holes will simply be repelled and what will remain on

5671-448: The body) are highly doped as signified by a "+" sign after the type of doping. If the MOSFET is an n-channel or nMOS FET, then the source and drain are n+ regions and the body is a p region. If the MOSFET is a p-channel or pMOS FET, then the source and drain are p+ regions and the body is a n region. The source is so named because it is the source of the charge carriers (electrons for n-channel, holes for p-channel) that flow through

5778-406: The channel in whole or in part, they are referred to as raised source/drain regions. The operation of a MOSFET can be separated into three different modes, depending on the voltages at the terminals. In the following discussion, a simplified algebraic model is used. Modern MOSFET characteristics are more complex than the algebraic model presented here. For an enhancement-mode, n-channel MOSFET ,

5885-408: The channel; similarly, the drain is where the charge carriers leave the channel. The occupancy of the energy bands in a semiconductor is set by the position of the Fermi level relative to the semiconductor energy-band edges. With sufficient gate voltage, the valence band edge is driven far from the Fermi level, and holes from the body are driven away from the gate. At larger gate bias still, near

5992-498: The common resolution of most smartphone screens at the time , and introduced multi-touch to phones, which allowed gestures such as "pinching" to zoom in or out on photos, maps, and web pages. The iPhone was notable as being the first device of its kind targeted at the mass market to abandon the use of a stylus, keyboard, or keypad typical of contemporary smartphones, instead using a large touchscreen for direct finger input as its main means of interaction. The iPhone's operating system

6099-486: The company announced that it would also exit the hardware market to focus more on software and its enterprise middleware, and began to license the BlackBerry brand and its Android distribution to third-party OEMs such as TCL for future devices. In September 2013, Microsoft announced its intent to acquire Nokia's mobile device business for $ 7.1 billion, as part of a strategy under CEO Steve Ballmer for Microsoft to be

6206-414: The conduction band (valence band) then the semiconductor type will be of n-type (p-type). When the gate voltage is increased in a positive sense (for the given example), this will shift the intrinsic energy level band so that it will curve downwards towards the valence band. If the Fermi level lies closer to the valence band (for p-type), there will be a point when the Intrinsic level will start to cross

6313-425: The course of the decade, the two platforms became a clear duopoly in smartphone sales and market share, with BlackBerry, Windows Phone, and other operating systems eventually stagnating to little or no measurable market share. In 2015, BlackBerry began to pivot away from its in-house mobile platforms in favor of producing Android devices, focusing on a security-enhanced distribution of the software. The following year,

6420-422: The current flow between drain and source. This is known as enhancement mode. The traditional metal–oxide–semiconductor (MOS) structure is obtained by growing a layer of silicon dioxide ( SiO 2 ) on top of a silicon substrate, commonly by thermal oxidation and depositing a layer of metal or polycrystalline silicon (the latter is commonly used). As silicon dioxide is a dielectric material, its structure

6527-731: The depletion layer and C ox {\displaystyle C_{\text{ox}}} = capacitance of the oxide layer. This equation is generally used, but is only an adequate approximation for the source tied to the bulk. For the source not tied to the bulk, the subthreshold equation for drain current in saturation is I D ≈ I D0 e V G − V th n V T e − V S V T . {\displaystyle I_{\text{D}}\approx I_{\text{D0}}e^{\frac {V_{\text{G}}-V_{\text{th}}}{nV_{\text{T}}}}e^{-{\frac {V_{\text{S}}}{V_{\text{T}}}}}.} In

SECTION 60

#1732776729694

6634-461: The device could be used as a digital cellular telephone. In June 1999 Qualcomm released the "pdQ Smartphone", a CDMA digital PCS smartphone with an integrated Palm PDA and Internet connectivity. Subsequent landmark devices included: In 1999, Japanese wireless provider NTT DoCoMo launched i-mode , a new mobile internet platform which provided data transmission speeds up to 9.6 kilobits per second, and access web services available through

6741-467: The device may be referred to as a metal-insulator-semiconductor FET (MISFET). Compared to the MOS capacitor, the MOSFET includes two additional terminals ( source and drain ), each connected to individual highly doped regions that are separated by the body region. These regions can be either p or n type, but they must both be of the same type, and of opposite type to the body region. The source and drain (unlike

6848-474: The early 1990s, IBM engineer Frank Canova realised that chip-and-wireless technology was becoming small enough to use in handheld devices . The first commercially available device that could be properly referred to as a "smartphone" began as a prototype called "Angler" developed by Canova in 1992 while at IBM and demonstrated in November of that year at the COMDEX computer industry trade show. A refined version

6955-468: The effect of thermal energy on the Fermi–Dirac distribution of electron energies which allow some of the more energetic electrons at the source to enter the channel and flow to the drain. This results in a subthreshold current that is an exponential function of gate-source voltage. While the current between drain and source should ideally be zero when the transistor is being used as a turned-off switch, there

7062-424: The electron is now fixed onto the atom and immobile. As the voltage at the gate increases, there will be a point at which the surface above the depletion region will be converted from p-type into n-type, as electrons from the bulk area will start to get attracted by the larger electric field. This is known as inversion . The threshold voltage at which this conversion happens is one of the most important parameters in

7169-597: The form of the mobile devices in terms of being non-planar, one can also have skin devices and tiny dust-sized devices. Dust refers to miniaturized devices without direct HCI interfaces, e.g., micro-electromechanical systems ( MEMS ), ranging from nanometers through micrometers to millimeters. See also Smart dust . Skin : fabrics based upon light emitting and conductive polymers and organic computer devices. These can be formed into more flexible non-planar display surfaces and products such as clothes and curtains, see OLED display . Also, see smart device . Although mobility

7276-413: The gate leads to a higher electron density in the inversion layer and therefore increases the current flow between the source and drain. For gate voltages below the threshold value, the channel is lightly populated, and only a very small subthreshold leakage current can flow between the source and the drain. When a negative gate-source voltage (positive source-gate) is applied, it creates a p-channel at

7383-455: The gate reduces the conductivity. The "metal" in the name MOSFET is sometimes a misnomer , because the gate material can be a layer of polysilicon (polycrystalline silicon). Similarly, "oxide" in the name can also be a misnomer, as different dielectric materials are used with the aim of obtaining strong channels with smaller applied voltages. The MOSFET is by far the most common transistor in digital circuits, as billions may be included in

7490-408: The gate voltage at which the volume density of electrons in the inversion layer is the same as the volume density of holes in the body is called the threshold voltage . When the voltage between transistor gate and source ( V G ) exceeds the threshold voltage ( V th ), the difference is known as overdrive voltage . This structure with p-type body is the basis of the n-type MOSFET, which requires

7597-464: The iPhone; Palm unveiled a new platform known as webOS for its Palm Pre in late-2009 to replace Palm OS , which featured a focus on a task-based "card" metaphor and seamless synchronization and integration between various online services (as opposed to the then-conventional concept of a smartphone needing a PC to serve as a "canonical, authoritative repository" for user data). HP acquired Palm in 2010 and released several other webOS devices, including

7704-417: The increase in power consumption due to gate current leakage, a high-κ dielectric is used instead of silicon dioxide for the gate insulator, while polysilicon is replaced by metal gates (e.g. Intel , 2009). The gate is separated from the channel by a thin insulating layer, traditionally of silicon dioxide and later of silicon oxynitride . Some companies use a high-κ dielectric and metal gate combination in

7811-520: The increasing use of smartphones with rapidly improving camera technology for casual photography, easier image manipulation , and abilities to directly share photos through the use of apps and web-based services. By 2011, cell phones with integrated cameras were selling hundreds of millions per year. In 2015, digital camera sales were 35.395 million units or only less than a third of digital camera sales numbers at their peak and also slightly less than film camera sold number at their peak. Contributing to

7918-818: The lack of channel region near the drain. Although the channel does not extend the full length of the device, the electric field between the drain and the channel is very high, and conduction continues. The drain current is now weakly dependent upon drain voltage and controlled primarily by the gate-source voltage, and modeled approximately as: I D = μ n C ox 2 W L [ V GS − V th ] 2 [ 1 + λ V DS ] . {\displaystyle I_{\text{D}}={\frac {\mu _{n}C_{\text{ox}}}{2}}{\frac {W}{L}}\left[V_{\text{GS}}-V_{\text{th}}\right]^{2}\left[1+\lambda V_{\text{DS}}\right].} The additional factor involving λ,

8025-531: The legacy BlackBerry OS with a revamped, QNX -based platform known as BlackBerry 10 , with the all-touch BlackBerry Z10 and keyboard-equipped Q10 as launch devices. In 2010, Microsoft unveiled a replacement for Windows Mobile known as Windows Phone , featuring a new touchscreen-centric user interface built around flat design and typography, a home screen with "live tiles" containing feeds of updates from apps, as well as integrated Microsoft Office apps. In February 2011, Nokia announced that it had entered into

8132-545: The main image with a macro focus shot . In 2007 the Nokia N95 was notable as a smartphone that had a 5.0 Megapixel (MP) camera, when most others had cameras with around 3 MP or less than 2 MP. Some specialized feature phones like the LG Viewty , Samsung SGH-G800 , and Sony Ericsson K850i , all released later that year, also had 5.0 MP cameras. By 2010 5.0 MP cameras were common; a few smartphones had 8.0 MP cameras and

8239-429: The mobile device has been marked by increasing technological convergence . Early mobile devices—such as pocket calculators , portable media players , satellite navigation devices , and digital cameras —excelled at their intended use but were not multifaceted. Personal digital assistants (PDAs) proliferated in the 1990s as a way to quickly write down notes, schedule business appointments, and set personal reminders, as

8346-783: The most common mobile device in the world, in terms of quantity sold, owing to their great convergence of technologies. By the early 2010s, mobile devices began integrating sensors such as accelerometers , magnetometers , and gyroscopes , allowing the detection of orientation and motion. Mobile devices may provide biometric user authentication, such as face recognition or fingerprint recognition. Handheld devices such as enterprise digital assistants have become more rugged for use in mobile field management . This involves tasks such as digitizing notes, sending and receiving invoices , asset management , recording signatures, managing parts, and scanning barcodes and RFID tags. In 2009, developments in mobile collaboration systems enabled

8453-670: The platform such as online shopping. NTT DoCoMo's i-mode used cHTML , a language which restricted some aspects of traditional HTML in favor of increasing data speed for the devices. Limited functionality, small screens and limited bandwidth allowed for phones to use the slower data speeds available. The rise of i-mode helped NTT DoCoMo accumulate an estimated 40 million subscribers by the end of 2001, and ranked first in market capitalization in Japan and second globally. Japanese cell phones increasingly diverged from global standards and trends to offer other forms of advanced services and smartphone-like functionality that were specifically tailored to

8560-534: The popularity of mobile gaming , the gambling industry started offering casino games on mobile devices, which led to the inclusion of these devices in the anti-hazard legislature as devices that could potentially be used for illegal gambling. Additional potentially unlawful actions could encompass the utilization of mobile devices in disseminating explicit material involving minors. Moreover, the legitimate adult entertainment sector's incorporation of mobile apps and technology to advance its operations raises concerns. There

8667-495: The preprint of their article in December 1956 to all his senior staff, including Jean Hoerni , who would later invent the planar process in 1959 while at Fairchild Semiconductor . After this, J.R. Ligenza and W.G. Spitzer studied the mechanism of thermally grown oxides, fabricated a high quality Si/ SiO 2 stack and published their results in 1960. Following this research, Mohamed Atalla and Dawon Kahng proposed

8774-526: The rest of the world. Phones that made effective use of any significant data connectivity were still rare outside Japan until the introduction of the Danger Hiptop in 2002, which saw moderate success among U.S. consumers as the T-Mobile Sidekick. Later, in the mid-2000s, business users in the U.S. started to adopt devices based on Microsoft's Windows Mobile , and then BlackBerry smartphones from Research In Motion . American users popularized

8881-412: The rise in popularity of smartphones being used over dedicated cameras for photography, smaller pocket cameras have difficulty producing bokeh in images, but nowadays, some smartphones have dual-lens cameras that reproduce the bokeh effect easily, and can even rearrange the level of bokeh after shooting. This works by capturing multiple images with different focus settings, then combining the background of

8988-659: The rising popularity of the iPhone in the late 2000s, the majority of smartphones have featured thin, slate-like form factors with large, capacitive touch screens with support for multi-touch gestures rather than physical keyboards. Most modern smartphones have the ability for users to download or purchase additional applications from a centralized app store . They often have support for cloud storage and cloud synchronization, and virtual assistants . Smartphones have largely replaced personal digital assistant (PDA) devices, handheld/palm-sized PCs , portable media players (PMP), point-and-shoot cameras , camcorders , and, to

9095-404: The same surface. They showed that silicon dioxide insulated, protected silicon wafers and prevented dopants from diffusing into the wafer. At Bell Labs, the importance of Frosch and Derick technique and transistors was immediately realized. Results of their work circulated around Bell Labs in the form of BTL memos before being published in 1957. At Shockley Semiconductor , Shockley had circulated

9202-399: The semiconductor surface the conduction band edge is brought close to the Fermi level, populating the surface with electrons in an inversion layer or n-channel at the interface between the p region and the oxide. This conducting channel extends between the source and the drain, and current is conducted through it when a voltage is applied between the two electrodes. Increasing the voltage on

9309-562: The standalone handset can when necessary be inserted into a tablet -sized screen unit with integrated supportive battery and used as such. In 2013 and 2014, Samsung experimented with the hybrid combination of compact camera and smartphone, releasing the Galaxy S4 Zoom and K Zoom , each equipped with integrated 10× optical zoom lens and manual parameter settings (including manual exposure and focus) years before these were widely adapted among smartphones. The S4 Zoom additionally has

9416-418: The surface of the n region, analogous to the n-channel case, but with opposite polarities of charges and voltages. When a voltage less negative than the threshold value (a negative voltage for the p-channel) is applied between gate and source, the channel disappears and only a very small subthreshold current can flow between the source and the drain. The device may comprise a silicon on insulator device in which

9523-410: The surface will be immobile (negative) atoms of the acceptor type, which creates a depletion region on the surface. A hole is created by an acceptor atom, e.g., boron, which has one less electron than a silicon atom. Holes are not actually repelled, being non-entities; electrons are attracted by the positive field, and fill these holes. This creates a depletion region where no charge carriers exist because

9630-541: The task key to simulate a short menu key press, as with home button to search. More recent "bezel-less" types have their screen surface space extended to the unit's front bottom to compensate for the display area lost for simulating the navigation keys. While virtual keys offer more potential customizability, their location may be inconsistent among systems depending on screen rotation and software used. Multiple vendors attempted to update or replace their existing smartphone platforms and devices to better-compete with Android and

9737-466: The term "CrackBerry" in 2006 due to the BlackBerry's addictive nature. In the U.S., the high cost of data plans and relative rarity of devices with Wi-Fi capabilities that could avoid cellular data network usage kept adoption of smartphones mainly to business professionals and " early adopters ." Outside the U.S. and Japan, Nokia was seeing success with its smartphones based on Symbian , originally developed by Psion for their personal organisers, and it

9844-417: The thermal voltage V T = k T / q {\displaystyle V_{\text{T}}=kT/q} and the slope factor n is given by: n = 1 + C dep C ox , {\displaystyle n=1+{\frac {C_{\text{dep}}}{C_{\text{ox}}}},} with C dep {\displaystyle C_{\text{dep}}} = capacitance of

9951-443: The three operational modes are: When V GS < V th : where V GS {\displaystyle V_{\text{GS}}} is gate-to-source bias and V th {\displaystyle V_{\text{th}}} is the threshold voltage of the device. According to the basic threshold model, the transistor is turned off, and there is no conduction between drain and source. A more accurate model considers

10058-485: The time that a touchscreen could not completely replace a physical keyboard and buttons. Android is based around a modified Linux kernel, again providing more power than mobile operating systems adapted from PDAs and feature phones. The first Android device, the horizontal-sliding HTC Dream , was released in September 2008. In 2012, Asus started experimenting with a convertible docking system named PadFone , where

10165-480: The use of handheld devices that combine video, audio, and on-screen drawing capabilities to enable multi-party conferencing in real-time, independent of location. Handheld computers are available in a variety of form factors, including smartphones , handheld PDAs , ultra-mobile PCs and tablet computers ( Palm OS , WebOS ). Users can watch television through the Internet by IPTV on some mobile devices. Mobile television receivers have existed since 1960, and, in

10272-518: The use of the cloud . Although a common form of mobile device, a smartphone, has a display, another perhaps even more common form of smart computing device, the smart card , e.g., used as a bank card or travel card, does not have a display. This mobile device often has a CPU and memory but needs to connect or be inserted into a reader to display its internal data or state. There are many kinds of mobile devices, designed for different applications. They include, but are not limited to: The history of

10379-421: The valence band), the semiconductor type changes at the surface as dictated by the relative positions of the Fermi and Intrinsic energy levels. A MOSFET is based on the modulation of charge concentration by a MOS capacitance between a body electrode and a gate electrode located above the body and insulated from all other device regions by a gate dielectric layer. If dielectrics other than an oxide are employed,

10486-414: The world population were smartphone users as of 2020. Early smartphones were marketed primarily towards the enterprise market, attempting to bridge the functionality of standalone PDA devices with support for cellular telephony , but were limited by their bulky form, short battery life , slow analog cellular networks, and the immaturity of wireless data services. These issues were eventually resolved with

10593-748: Was about 100 times slower than contemporary bipolar transistors and was initially seen as inferior. Nevertheless, Kahng pointed out several advantages of the device, notably ease of fabrication and its application in integrated circuits . Usually the semiconductor of choice is silicon . Some chip manufacturers, most notably IBM and Intel , use an alloy of silicon and germanium ( SiGe ) in MOSFET channels. Many semiconductors with better electrical properties than silicon, such as gallium arsenide , do not form good semiconductor-to-insulator interfaces, and thus are not suitable for MOSFETs. Research continues on creating insulators with acceptable electrical characteristics on other semiconductor materials. To overcome

10700-488: Was also a shift away from older operating systems (which older phones supported and which were adapted from PDAs and feature phones ) to an operative system powerful enough to not require using a limited, stripped down web browser that can only render pages specially formatted using technologies such as WML , cHTML , or XHTML and instead ran a version of Apple's Safari browser that could render full websites not specifically designed for mobile phones. Later Apple shipped

10807-506: Was manufactured by Mitsubishi Electric , which integrated features with its own cellular radio technologies. It featured a liquid-crystal display (LCD) and PC Card support. The Simon was commercially unsuccessful, particularly due to its bulky form factor and limited battery life , using NiCad batteries rather than the nickel–metal hydride batteries commonly used in mobile phones in the 1990s, or lithium-ion batteries used in modern smartphones. The term "smart phone" (in two words)

10914-434: Was marketed to consumers in 1994 by BellSouth under the name Simon Personal Communicator . In addition to placing and receiving cellular calls , the touchscreen-equipped Simon could send and receive faxes and emails . It included an address book, calendar, appointment scheduler, calculator, world time clock, and notepad, as well as other visionary mobile applications such as maps, stock reports and news. The IBM Simon

11021-694: Was not coined until a year after the introduction of the Simon, appearing in print as early as 1995, describing AT&T's PhoneWriter Communicator. The term "smartphone" (as one word) was first used by Ericsson in 1997 to describe a new device concept, the GS88 . Beginning in the mid-to-late 1990s, many people who had mobile phones carried a separate dedicated PDA device, running early versions of operating systems such as Palm OS , Newton OS , Symbian or Windows CE / Pocket PC . These operating systems would later evolve into early mobile operating systems . Most of

11128-538: Was so high in Japan that the companies did not feel the need to look elsewhere for additional profits. The rise of 3G technology in other markets and non-Japanese phones with powerful standardized smartphone operating systems , app stores , and advanced wireless network capabilities allowed non-Japanese phone manufacturers to finally break in to the Japanese market, gradually adopting Japanese phone features like emojis , mobile payments, NFC, etc. and spreading them to

11235-544: Was the Kyocera Visual Phone VP-210 , released in Japan in May 1999. It was called a "mobile videophone" at the time, and had a 110,000- pixel front-facing camera . It could send up to two images per second over Japan's Personal Handy-phone System (PHS) cellular network , and store up to 20 JPEG digital images , which could be sent over e-mail . The first mass-market camera phone was the J-SH04 ,

11342-479: Was the LG Prada , announced by LG in December 2006. This was a fashionable feature phone created in collaboration with Italian luxury designer Prada with a 3" 240 x 400 pixel screen, a 2-Megapixel digital camera with 144p video recording ability, an LED flash , and a miniature mirror for self portraits. In January 2007, Apple Computer introduced the iPhone . It had a 3.5" capacitive touchscreen with twice

11449-653: Was the most popular smartphone OS in Europe during the middle to late 2000s. Initially, Nokia's Symbian smartphones were focused on business with the Eseries , similar to Windows Mobile and BlackBerry devices at the time. From 2002 onwards, Nokia started producing consumer-focused smartphones, popularized by the entertainment-focused Nseries . Until 2010, Symbian was the world's most widely used smartphone operating system. The touchscreen personal digital assistant (PDA)–derived nature of adapted operating systems like Palm OS ,

#693306