scholarly journals Infrared analysis on hydrogen content and Si-H bonding configurations of hydrogenated amorphous silicon films

2003 ◽  
Vol 52 (1) ◽  
pp. 169
Author(s):  
Luo Zhi ◽  
Lin Xuan-Ying ◽  
Lin Shun-Hui ◽  
Yu Chu-Ying ◽  
Lin Kui-Xun ◽  
...  
Keyword(s):  
Amorphous Silicon ◽  
Hydrogen Content ◽  
Hydrogenated Amorphous Silicon ◽  
Silicon Films ◽  
Infrared Analysis ◽  
Hydrogenated Amorphous

How much hydrogen and voids are energetically stable in silicon thin films?

2004 ◽  
Vol 813 ◽  
Author(s):  
Anna Fontcuberta i Morral ◽  
Holger Vach ◽  
Pere Roca i Cabarrocas
Keyword(s):  
Thin Films ◽  
Amorphous Silicon ◽  
Void Fraction ◽  
Hydrogen Content ◽  
Formation Energy ◽  
Hydrogenated Amorphous Silicon ◽  
Silicon Films ◽  
Homogeneous Distribution ◽  
Silicon Thin Films ◽  
Hydrogenated Amorphous

ABSTRACTWe have developed a model to account for the effects of hydrogen and voids on the structural stability of silicon thin films. The model is based on both experiments and theory. First, hydrogenated amorphous silicon films (a-Si:H) with various hydrogen contents were obtained by Plasma Enhanced Chemical Vapor Deposition. A linear correlation between hydrogen content and void fraction was observed. By tuning the deposition conditions, polymorphous silicon films with hydrogen contents up to 15%, very small void fractions (0.5%) and excellent electronic properties were also obtained. Density Functional Theory (DFT) calculations were performed to determine the formation energy for four types of silicon tetrahedra of the form Si-SinH4−n (n=1, 2, 3, 4). In our model, these tetrahedral units are considered as the building blocks of the silicon thin films. Considering a homogeneous distribution of hydrogen in the solid, the proportion of the different SiSinH4−n tetrahedra as a function of the hydrogen concentration was calculated. Then, the formation energy of hydrogenated amorphous silicon (a-Si:H) was calculated as a function of the hydrogen content and for various porosities. The model predicts that hydrogen incorporation does render the a-Si:H structure unstable for different hydrogen contents depending on the void fraction. Our results show that polymorphous silicon films with hydrogen concentrations up to 15% can be as stable as standard amorphous silicon with 2% hydrogen content, provided that the presence of hydrogen is not associated with the incorporation of porosity in the film.

Reduction of Si-H2 Bond Content in Hydrogenated Amorphous Silicon Prepared by Mercury-Sensitized Photochemical Vapor Deposition

1990 ◽  
Vol 192 ◽  
Author(s):  
N. Sakuma ◽  
H. Nozaki ◽  
T. Niiyama ◽  
H. Ito
Keyword(s):  
Light Intensity ◽  
Amorphous Silicon ◽  
Hydrogen Content ◽  
Vapor Deposition ◽  
Hydrogenated Amorphous Silicon ◽  
Silicon Films ◽  
The Other ◽  
Photochemical Vapor Deposition ◽  
Hydrogenated Amorphous ◽  
Deposition Conditions

ABSTRACTThe ratio of Si-H2 bonds to hydrogen content in hydrogenated amorphous silicon films, prepared by mercury-sensitized photochemical vapor deposition, depends on the deposition conditions, in particular on the distance between the substrate and the light-transparent window.The ratio is reduced from 20 % to 8 % by decreasing the distance from 30 mm to 8 mm. On the other hand, the hydrogen content remains constant at 15 at.%. Decreasing the distance has been found to be almost equivalent to increasing the light intensity, especially 254 nm-light intensity.

Effect of Annealing on Microstructure in (Doped and Undoped) Hydrogenated Amorphous Silicon Films

2014 ◽  
Vol 1666 ◽  
Author(s):  
W. Beyer ◽  
W. Hilgers ◽  
D. Lennartz ◽  
F.C. Maier ◽  
N.H. Nickel ◽  
...  
Keyword(s):  
Amorphous Silicon ◽  
Hydrogen Content ◽  
Hydrogenated Amorphous Silicon ◽  
Silicon Films ◽  
Boron Doped ◽  
Scan Time ◽  
Laser Treatments ◽  
Laser Impact ◽  
Definition Of ◽  
Hydrogenated Amorphous

ABSTRACTLaser heating and annealing of hydrogenated amorphous silicon (a-Si:H) films is of interest for improved material properties. Due to the variety of possible laser treatments with regard to wavelength, pulse duration, scan time etc., the definition of laser impact on the material is a challenge which we try to approach by comparing properties of laser and oven treated materials. Here we report on the effect of oven heat treatment (up to TA= 575°C) on microstructure and hydrogen content of hydrogenated amorphous silicon films, as detected by measurements of infrared absorption and of effusion of hydrogen as well as of implanted helium. The latter technique has been found to measure isolated voids (cavities) of the size of silicon divacancies and larger. Undoped as well as phosphorus and boron doped plasma-deposited a-Si:H films of various hydrogen content (< 15 at.%) were investigated, including undoped device grade a-Si:H. The results show little indication for void-related microstructure in the as-deposited and annealed state for material with a concentration of silicon bonded hydrogen below 5 at. %. At higher hydrogen concentration, evidence is found that hydrogen out-diffusion due to annealing causes isolated voids in concentrations up to about 1020 cm-3. A possible mechanism for the annealing induced (micro-)void generation is discussed.

Influence of Hydrogen Content and Si-H Bond Structure on Photocreated Dangling Bonds in Hydrogenated Amorphous Silicon Films

1996 ◽  
Vol 35 (Part 1, No. 8) ◽  
pp. 4409-4412 ◽  
Author(s):  
Qing Zhang ◽  
Takayuki Nishino ◽  
Hideki Takashima ◽  
Minoru Kumeda ◽  
Tatsuo Shimizu
Keyword(s):  
Amorphous Silicon ◽  
Hydrogen Content ◽  
Hydrogenated Amorphous Silicon ◽  
Silicon Films ◽  
Dangling Bonds ◽  
Hydrogenated Amorphous
Sign in / Sign up

Export Citation Format

Share Document