Amorphous silicon

About: Amorphous silicon is a research topic. Over the lifetime, 26777 publications have been published within this topic receiving 423234 citations.

Effects of thermal annealing on the refractive index of amorphous silicon produced by ion implantation

Abstract: Precise infrared reflection measurements of the refractive index of silicon show that there are two well‐defined optical states of amorphous silicon produced by ion implantation One is the as‐implanted amorphous state which is the high refractive index state produced by high fluence implantation of Si or P ions into Si samples The other state, which has a refractive index intermediate between the as‐implanted and crystalline values, is induced by thermal annealing and is thermally stable until epitaxial recrystallization occurs

Amorphous Silicon Microbolometer Technology

Abstract: Highly sensitive hydrogenated amorphous silicon (a-Si:H) microbolometer arrays have been developed that take advantage of the high temperature coefficient of resistance (TCR) of aSi:H and its relatively high optical absorption coefficient. TCR is an important design parameter and depends on material properties such as doping concentration. Ultra-thin (∼2000 A) aSiNx:H/a-Si:H/ a-SiNx:H membranes with low thermal mass suspended over silicon readout integrated circuits are built using RF plasma enhanced chemical vapor deposition (PECVD) and surface micromachining techniques. The IR absorptance of the bolometer detectors is enhanced by using quarter-wave resonant cavity structures and thin-film metal absorber layers. To ensure high thermal isolation the microbolometer arrays are vacuum packaged using wafer level vacuum packaging. Imaging applications include a 120×160 a-Si:H bolometer pixel array IR camera operating at ambient temperature. Non-imaging applications are multi-channel detectors for gas sensing systems.

A new type of amorphous silicon photovoltaic cell generating more than 2.0 V

Abstract: A new type of plasma‐deposited amorphous silicon photovoltaic cell having a horizontally multilayered p‐i‐n unit‐cell structure has been developed. The open‐circuit voltage Voc is nearly proportional to the number of repetitions of the p‐i‐n unit cell. Almost‐constant energy‐conversion efficiencies of around 4% have been obtained with Voc ranging from 0.6 to 2.4 V by applying a simple optimum design rule to the cell‐construction parameters.

Image forming method

Abstract: PURPOSE:To obtain good images by performing electrolytic reaction by using the hydrogenated amorphous silicon of controlled electrical characteristics as a photosensitive layer CONSTITUTION:A photosensitive layer substrate 21 made by depositing a hydrogenated amorphous silicon layer 12 on a conductive substrate 11 is put into electrolyte 23 For example, an aqueous soln of zinc acetate of 001mol/l is used as the electrolyte Next, a subject 26 is imaged on the photosensitive layer substrate 21 through a transparent wall 28 by a lamp 25 and a lens system 27 In this state, a constant voltage DC power source 29 is connected in a manner that a counter electrode 24 acts as anode and the conductive substrate 11 as cathode, and a voltage of about 5V is applied Thence, according to the exposure, zinc will deposit on the surface of the layer 12

PROM electrically written by solid phase epitaxy

Abstract: A memory cell, having a doped amorphous silicon layer, is formed on a thin layer of silicon alloy which is on a single crystal silicon substrate. The cell is programmed by applying a voltage between a surface contact and the substrate to cause a crystal column to form in the amorphous layer between the substrate and the contact by solid-phase epitaxial growth. A diode is formed between the contact and the substrate by the selection of impurity levels and conductivity type of the amorphous layer and substrate and the selection of the silicon alloy. The cross-sectional area of the column is selectable to provide a multi storage level cell.