Two-level systems in hydrogenated amorphous silicon: NMR studies

1985 ◽  
Vol 32 (9) ◽  
pp. 6062-6065 ◽  
Author(s):  
J. B. Boyce ◽  
M. Stutzmann ◽  
S. E. Ready
Keyword(s):  
Amorphous Silicon ◽  
Hydrogenated Amorphous Silicon ◽  
Nmr Studies ◽  
Two Level Systems ◽  
Hydrogenated Amorphous

scholarly journals Decoupling between propagating acoustic waves and two-level systems in hydrogenated amorphous silicon

2021 ◽  
Vol 104 (2) ◽  
Author(s):  
M. Molina-Ruiz ◽  
H. C. Jacks ◽  
D. R. Queen ◽  
T. H. Metcalf ◽  
X. Liu ◽  
...  
Keyword(s):  
Amorphous Silicon ◽  
Acoustic Waves ◽  
Hydrogenated Amorphous Silicon ◽  
Two Level Systems ◽  
Hydrogenated Amorphous

scholarly journals Two-level systems and growth-induced metastability in hydrogenated amorphous silicon

2020 ◽  
Vol 7 (9) ◽  
pp. 095201
Author(s):  
M Molina-Ruiz ◽  
H C Jacks ◽  
D R Queen ◽  
Q Wang ◽  
R S Crandall ◽  
...  
Keyword(s):  
Amorphous Silicon ◽  
Hydrogenated Amorphous Silicon ◽  
Two Level Systems ◽  
Hydrogenated Amorphous

Voids in Hydrogenated Amorphous Silicon: A Comparison of ab initio Simulations and Proton NMR Studies

2008 ◽  
Vol 1066 ◽  
Author(s):  
Sudeshna Chakraborty ◽  
David C Bobela ◽  
P C Taylor ◽  
D. A. Drabold
Keyword(s):  
Ab Initio ◽  
Amorphous Silicon ◽  
Nearest Neighbor ◽  
Hydrogenated Amorphous Silicon ◽  
Simulation Methods ◽  
Hydrogen Atoms ◽  
Nmr Studies ◽  
Ab Initio Simulations ◽  
Nmr Data ◽  
Hydrogenated Amorphous

ABSTRACTRecently, a new hydrogen NMR signal has been observed in a number of PECVD prepared hydrogenated amorphous silicon (a-Si:H) films of varying quality. It is speculated that the signal is the consequence of a dipolar-coupled hydrogen pair separated, on average, by 1.8 ± 0.1 Å. To elucidate the possible bonding configurations responsible for the NMR data of ref. [1], we have used ab initio simulation methods to determine a set of relaxed structures of a-Si:H with varying void sizes and H-concentrations. Models containing two isolated hydrogen atoms indicate a preferred H-H distance of approximately 1.8 Å when the two atoms bond to nearest neighbor silicon atoms. This separation also occurs for models containing small, hydrogenated voids, but the configurations giving rise to this H-H distance do not appear to be unique. For larger voids, a proton separation of about 2.4Å is seen, as noted previously [2]. There appears to be consistency between the computed structures and the NMR data for configurations consisting of isolated hydrogen pairs or for clusters of an even number of hydrogen atoms with the constraint that the average H-H distance is 1.8 Å. In this paper, we will discuss the most probable bonding configurations of clustered hydrogen based upon the extent of the NMR data and simulated structures.

NMR studies of hydrogen microstructures in hydrogenated amorphous silicon films

1994 ◽  
Vol 3 (10) ◽  
pp. 730-735
Author(s):  
Qu Xue-xuan ◽  
Chen Kun-ji ◽  
Chen Mao-rui ◽  
Hu Cheng ◽  
Li Zhi-feng ◽  
...  
Keyword(s):  
Amorphous Silicon ◽  
Hydrogenated Amorphous Silicon ◽  
Silicon Films ◽  
Nmr Studies ◽  
Hydrogenated Amorphous

BONDING IN HYDROGENATED AMORPHOUS SILICON

1981 ◽  
Vol 42 (C4) ◽  
pp. C4-773-C4-777 ◽  
Author(s):  
H. R. Shanks ◽  
F. R. Jeffrey ◽  
M. E. Lowry
Keyword(s):  
Amorphous Silicon ◽  
Hydrogenated Amorphous Silicon ◽  
Hydrogenated Amorphous

High Rate Deposition of Stable Hydrogenated Amorphous Silicon in Transition from Amorphous to Microcrystalline Silicon

2003 ◽  
Vol 762 ◽  
Author(s):  
Guofu Hou ◽  
Xinhua Geng ◽  
Xiaodan Zhang ◽  
Ying Zhao ◽  
Junming Xue ◽  
...  
Keyword(s):  
Phase Transition ◽  
Amorphous Silicon ◽  
Hydrogenated Amorphous Silicon ◽  
Chemical Vapor ◽  
High Rate ◽  
Very High Frequency ◽  
High Quality ◽  
Working Pressure ◽  
Hydrogen Dilution ◽  
Hydrogenated Amorphous

AbstractHigh rate deposition of high quality and stable hydrogenated amorphous silicon (a-Si:H) films were performed near the threshold of amorphous to microcrystalline phase transition using a very high frequency plasma enhanced chemical vapor deposition (VHF-PECVD) method. The effect of hydrogen dilution on optic-electronic and structural properties of these films was investigated by Fourier-transform infrared (FTIR) spectroscopy, Raman scattering and constant photocurrent method (CPM). Experiment showed that although the phase transition was much influenced by hydrogen dilution, it also strongly depended on substrate temperature, working pressure and plasma power. With optimized condition high quality and high stable a-Si:H films, which exhibit σph/σd of 4.4×106 and deposition rate of 28.8Å/s, have been obtained.

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