Arsenic-doped-silicon

Similar depth profiles are routinely done for phosphorus and arsenic-doped silicon films. 

Implantation. Ziegler and co-workers (1,14,24,25) introduced NDP by determining the range and shape of boron implantation distributions in intrinsic and doped silicon wafers. With the resultant profiles, they were able to calculate diffusion coefficients for boron in crystalline, amorphous, and arsenic-doped silicon. Since little experimental data existed for the case of boron to judge the validity of the current range theories, the shape of the boron profiles from NDP were of great interest. NDP and other techniques have since been able to show that a Pearson IV model rather than a gaussian profile is required to describe accurately the Implant distribution (21,26-28). 

ASTM F 723, Standard practice for conversion between resistivity and dopant density for boron-doped, phosphorus-doped, and arsenic-doped silicon. The 1999 annual book of ASTM standards, American Society for Testing and Materials. 

GenCorp Aerojet Electronic Systems Division, Azusa, CA Arsenic-doped Silicon (Si As)... 

Two 256X256-pixel arsenic-doped-silicon (Si As) impurity band conduction (IBC) hybrid detector arrays developed by Hughes Technology Center have been evaluated for space-based astronomy applications. Potential applications include instrumentation on orbiting astronomy platforms such as the Space Infrared Telescope Facility (SIRTF). 

Abstract. A new in ared camera (AIR Camera) has been developed at NASA - Ames Rraeaich Center for observations from gronnd-based telercopes. The heart of the camera is a Hu es 58 x 62 pixel Arsenic-doped Silicon detector array that has the spectral sensitivity range to allow observations in both the 10 and 20 micron atmospheric windows. 

The first demonstration of BIB detector used arsenic-doped silicon (Si As) is the IBC material. A schematic cross-section of a basic Si As BIB detector structure is shown in Figure 1. 

Semiconductor properties are imparted by doping its structure with boron, phosphorus, or arsenic atoms. Silicon is relatively inert chemically but is attacked by halogens and dilute alkalies. It has good optical transmission especially in the infra-red. 

HYDROGEN NEUTRALIZATION OF SHALLOW-DONOR IMPURITIES IN ARSENIC-DOPED EPILAYERS ON SILICON... 

In doped silicon (an extrinsic semiconductor) the doping element has either three or five valence electrons (one electron less or one electron more than the four valence electrons of silicon). Substituting an arsenic or phosphorus atom (five valence electrons) for a silicon atom in a silicon crystal provides an extra loosely-bound electron that is more easily excited into the CB than in the case of the pure silicon. In such an n-type semiconductor, most of the electrical conductivity is attributed... 

A different application of chemical equilibrium leads to an explanation of how the incorporation of defects and dopants depends on the growth conditions (Winer and Street 1989). Section S.l describes the unexpected rf power and gas concentration dependence of the dopant distribution coefficient, particularly for arsenic doping. A schematic diagram of the growth process is shown in Fig. 6.19, in which three-fold and four-fold silicon and dopants are deposited from the gas phase. The deposition reactions proposed for arsenic doping are... 

In phosphorus-doped silicon, the extra electrons from the phosphorus atoms are not needed to hold the crystal together. They are free to move and carry an electric current. Arsenic and antimony are also used to dope silicon. Both have five valence electrons. 

Semiconductors Germanium has the same type of structure and semiconducting properties as silicon. What type of semiconductor would you expect arsenic-doped germanium to be ... 

In 1983 the application of doped tin oxide films to silicon solar cells has been reported [5]. lida and coworkers realized a setup with the following characteristics 7sc = 14 mAcm", Kic = 800 mV, efficiency = 7.5 % and fill factor = 0.67. Vishwakarma et al. [166, 167] prepared arsenic-doped tin oxide films for silicon solar cells and investigated the diode properties of Sn02 As/Si02/n-Si and Sn02 As/n-Si cells. The barrier height 0 was 0.78-0.89 eV and 0.68-0.69 eV, respectively, and the reverse saturation current density 7u was 2-45 pAcm and 0.07-9.2 pAcm", respectively, with diode quality factors of 2.2-2.9 and 1.7-1.9. The optimized results for solar cell applications are given below... 

The linear photodiode array (LPDA) is a transducer developed to enable simultaneous measurement of light intensity at many wavelengths. The diode array consists of a number of semiconductors embedded in a single crystal in a one-dimensional linear array. A common procedure is to use a single crystal of doped silicon that is an n-type semiconductor. A small excess of a group 3A element, such as arsenic, is embedded into the surface at regular intervals. This creates local p-type semiconductors. The semiconductor device ideally has a cross-section such as that shown in Fig. 5.24. The surface contains a linear series or array of pn junctions, each of which is a photodiode. The individual diodes are called elements, channels, or pixels. 

Arsenic, a Group 5A element, can be used to dope silicon, a Group 4A element. This doping will produce (n-type/j type) doped silicon. 

Silicon is frequently doped with other substances. If aluminum atoms replace some silicon atoms, there are holes in the bonding orbitals, because aluminum has 13 electrons whereas silicon has 14. This makes the doped silicon into a p-type semiconductor that would conduct some electricity even at 0 K. (The p designation refers to the positive holes that can be thought of as moving around.) If arsenic atoms replace silicon atoms, the doped silicon becomes an n-type semiconductor, because arsenic atoms have five valence electrons instead of silicon s four valence electrons, and the fifth electron would be found in the 3d band. (The n designation refers to the conduction by negative electrons.)... 

A (a) Elements with two valence electrons, e.g.. Be, Sr, Cd, (b) elements with three valence electrons, e.g., B, Ga, In, (c) elements with six valence electrons, e.g., O, Se, Te. 25.5B Carbon can be combined with silicon to produce a semiconductor. Arsenic can be used to dope silicon to produce an -type semiconductor and gallium can be used to dope silicon to produce a p-type semiconductor. 

Hyperpure silicon can be doped with boron, gallium, phosphorus, or arsenic to produce silicon for use in transistors, solar cells, rectifiers, and other solid-state devices which are used extensively in the electronics and space-age industries. 

Fig. 5. Bipolar transistor (a) schematic and (b) doping profiles of A, arsenic ion implanted into the silicon of the emitter ( -type) B, boron ion implanted into the silicon of the base (p-type) C, antimony ion implanted into the buried layer ( -type) and D, the epi layer...

Silicon s atomic structure makes it an extremely important semiconductor. Highly purified silicon, doped with such elements as boron, phosphorus, and arsenic, is the basic material used in computer chips, transistors, sUicon diodes, and various other electronic circuits and electrical-current switching devices. Silicon of lesser purity is used in metallurgy as a reducing agent and as an alloying element in steel, brass, and bronze. 

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