Polycrystalline silicon

About: Polycrystalline silicon is a research topic. Over the lifetime, 19554 publications have been published within this topic receiving 198222 citations. The topic is also known as: polysilicon & poly-Si.

Rare-earth-containing glass material and substrate and device comprising such substrate

Abstract: A rare-earth-containing glass material having a composition, expressed in mole percentages on and oxide basis, comprising: SiO2: 66-75 Al2O3: 11-17 B2O3: 0-4 MgO: 1-6.5 CaO: 2-7 SrO: 0-4 BaO: 0-4 Y2O3: 0-4 La2O3: 0-4 Y2O3+La2O3: 0.1-4. The inclusion of Y2O3 and/or La2O3 in the composition reduces the T2.3 of the glass thereby allowing higher annealing-point glasses to be produced. The glass is particularly useful for low-temperature polycrystalline silicon-based semiconductor devices.

Xenon Flash Lamp Annealing of Poly-Si Thin Films

Abstract: We have investigated xenon (Xe) flash lamp annealing for the crystallization of amorphous silicon (a-Si) films for polycrystalline silicon (poly-Si) thin film transistors on glass substrates. The Xe flash lamp emits white light with a wavelength range of 400-800 nm for 40 μs, thereby instantaneously supplying the energy necessary to crystallize a-Si films to poly-Si films. The distance between electrodes in the lamp is 1000 mm, the bore diameter is 10 mm, and the peak voltage is up to 20 kV. The sample structure is a-Si (50 nm)/SiOx (100 nm) deposited on a glass substrate by plasma-enhanced chemical vapor deposition using SiH 4 gas. An average grain size of 500 nm is obtained without substrate heating during Xe flash lamp annealing when the light energy density is 1.82 J/cm 2 . The grain size is less than 50 nm at 1.55-1.78 J/cm 2 , and a significant grain growth occurs at 1.82 J/cm 2 . The light energy is absorbed by the whole a-Si film, because the Xe flash lamp emits light with a wide wavelength range of 400-800 nm. Therefore, when the light energy exceeds its threshold at which the a-Si film melting point is observed, a-Si films can be partially melted and subsequently crystallized at the top and bottom surfaces, thereby forming large-grain poly-Si.

Crystalline orientation of polycrystalline silicon with disklike grains produced by silicide-mediated crystallization of amorphous silicon

Abstract: Crystalline orientations of disklike grains in polycrystalline silicon (poly-Si) formed by silicide-mediated crystallization (SMC) of amorphous silicon (a-Si) have been studied and compared with those of needlelike crystallites. The disklike grain can be obtained by SMC of a-Si with a silicon–nitride cap on it and its size is as large as 42 μm by using the average Ni area density of 2.43×1014 cm−2 on the cap. On the other hand, the poly-Si crystallized without the cap layer is composed of needlelike crystallites. The electron diffraction (ED) patterns of transmission electron microscope (TEM) remain unchanged for the selected area from 1 to 10 μm diameter inside of the disklike grain, but the ED patterns of SMC poly-Si composed of needlelike crystallites show a ring pattern for the area of 10 μm diameter due to many crystalline orientations. Electron backscattered diffraction and TEM analysis indicate that each disk-like grain has a single orientation, but its orientation is not always the same as that of...

Trench resistor structures for compact semiconductor memory and logic devices

Abstract: A vertical trench etched several microns deep into the silicon extending into a buried diffusion region is used to confine a vertical interconnect element. This element can be a high resistivity undoped polycrystalline silicon load resistor, a medium resistivity doped polycrystalline silicon load resistor, or a low resistivity interconnect to the buried diffusion region. This new structure can be used in compact and scalable MOS and bipolar inverters and in bistable memory storage cells.