Dangling bond electron spin‐lattice relaxation in rf‐sputtered hydrogenated amorphous silicon and silicon carbide

1986 ◽  
Vol 49 (17) ◽  
pp. 1092-1094 ◽  
Author(s):  
S. Dey ◽  
D. R. Torgeson ◽  
R. G. Barnes
Keyword(s):  
Silicon Carbide ◽  
Amorphous Silicon ◽  
Electron Spin ◽  
Hydrogenated Amorphous Silicon ◽  
Lattice Relaxation ◽  
Spin Lattice Relaxation ◽  
Dangling Bond ◽  
Spin Lattice ◽  
Hydrogenated Amorphous

Change of Spin-Lattice Relaxation Time with Light Soaking for Defects in Hydrogenated Amorphous Silicon

1998 ◽  
Vol 37 (Part 1, No. 10) ◽  
pp. 5470-5473
Author(s):  
Wei-Chi Lai ◽  
Chun-Yen Chang ◽  
Meiso Yokoyama ◽  
Jen-Dar Guo ◽  
Jian-Shihn Tsang ◽  
...  
Keyword(s):  
Relaxation Time ◽  
Amorphous Silicon ◽  
Hydrogenated Amorphous Silicon ◽  
Lattice Relaxation ◽  
Lattice Relaxation Time ◽  
Spin Lattice Relaxation ◽  
Spin Lattice Relaxation Time ◽  
Spin Lattice ◽  
Hydrogenated Amorphous

Defects in Hydrogenated Amorphous Silicon Carbide Alloys using Electron Spin Resonance and Photothermal Deflection Spectroscopy

2009 ◽  
Vol 1153 ◽  
Author(s):  
Brian J. Simonds ◽  
Feng Zhu ◽  
Josh Gallon ◽  
Jian Hu ◽  
Arun Madan ◽  
...  
Keyword(s):  
Silicon Carbide ◽  
Electron Spin Resonance ◽  
Amorphous Silicon ◽  
Electron Spin ◽  
Carbon Concentration ◽  
Hydrogenated Amorphous Silicon ◽  
Photothermal Deflection Spectroscopy ◽  
Spin Resonance ◽  
Photothermal Deflection ◽  
Hydrogenated Amorphous

AbstractHydrogenated amorphous silicon carbide alloys are being investigated as a possible top photoelectrode in photoelectrochemical cells used for hydrogen production through water splitting. In order to be used as such, it is important that the effects of carbon concentration on bonding, and thus on the electronic and optical properties, is well understood. Electron spin resonance experiments were performed under varying experimental conditions to study the defect concentrations. The dominant defects are silicon dangling bonds. At room temperature, the spin densities varied between 1016 and 1018 spins/cm3 depending on the carbon concentration. Photothermal deflection spectroscopy, which is an extremely sensitive measurement of low levels of absorption in thin films, was performed to investigate the slope of the Urbach tail. These slopes are 78 meV for films containing the lowest carbon concentration and 98 meV for those containing the highest carbon concentration.

Effect of Light Soaking on the Local Motion of Hydrogen in Hydrogenated Amorphous Silicon

1994 ◽  
Vol 336 ◽  
Author(s):  
P. Hari ◽  
P. C. Taylor ◽  
R. A. Street
Keyword(s):  
Amorphous Silicon ◽  
Defect Density ◽  
Hydrogenated Amorphous Silicon ◽  
Lattice Relaxation ◽  
Lattice Relaxation Time ◽  
Spin Lattice Relaxation ◽  
Local Motion ◽  
Paramagnetic Defect ◽  
Hydrogenated Amorphous ◽  
Effect Of Light

ABSTRACTPrevious measurements of local hydrogen motion in intrinsic, doped, and compensated hydrogenated Amorphous silicon (a-Si:H) using the 1H nuclear magnetic resonance (NMR) dipolar echo method have shown that the local hydrogen motion is much faster than the macroscopic diffusion would indicate but that the local motion follows the same trends with doping and defect density as the macroscopic diffusion. We report the effect of light soaking on the local motion of hydrogen in hydrogenated Amorphous silicon. Measurements are presented on 10−3 P-doped a-Si:H at 297 K. After light soaking with infrared-filtered, white light of intensity -400 MW/cm2 for 75 hours, the electron spin resonance (ESR) spin density increases to -101 spins/cm After light soaking 1H NMR dipolar echo measurements on this sample show that the dipolar spin-lattice relaxation time, T1D, is ∼4 Ms. After thermal annealing at 190 C for two hours the value of T1Dreturns to its pre-irradiation value of ∼ 11 Ms. The local rate of motion, which scales with TID-1 thus increases with the paramagnetic defect density. The general implications of this result for descriptions of both microscopic and macroscopic Motion of hydrogen in a-Si:H are discussed.

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