Band offsets and deep defect distribution in hydrogenated amorphous silicon‐crystalline silicon heterostructures

1989 ◽  
Vol 55 (12) ◽  
pp. 1232-1234 ◽  
Author(s):  
John M. Essick ◽  
J. David Cohen
Keyword(s):  
Amorphous Silicon ◽  
Crystalline Silicon ◽  
Hydrogenated Amorphous Silicon ◽  
Defect Distribution ◽  
Band Offsets ◽  
Deep Defect ◽  
Hydrogenated Amorphous ◽  
Silicon Heterostructures

Conduction and Valence Band Offsets at the Hydrogenated Amorphous Silicon-Carbon/Crystalline Silicon Interface Via Capacitance Techniques

1993 ◽  
Vol 297 ◽  
Author(s):  
John M. Essick ◽  
Richard T. Mather ◽  
Murray S. Bennett ◽  
James Newton
Keyword(s):  
Amorphous Silicon ◽  
Band Gap ◽  
Valence Band ◽  
Crystalline Silicon ◽  
Hydrogenated Amorphous Silicon ◽  
Thick Layer ◽  
Band Offset ◽  
Band Offsets ◽  
Silicon Carbon ◽  
Hydrogenated Amorphous

Heterostructure Schottky diode samples each composed of a sub-micron thick layer of intrinsic hydrogenated amorphous silicon-carbon (a-Si1−xCx:H) deposited on an n-type crystalline silicon (c-Si) substrate are used to measure the a-Si1−xCx:H/c-Si band offsets via junction capacitance techniques. The samples range in carbon concentration from x=0.0−0.3. First, a thermally activated capacitance step due to the response of defects at the amorphous/crystalline interface is evident in capacitance vs. temperature spectra taken on all these samples. The bias-dependence of this step’s activation energy provides a direct measure of the a-Si1−xCx:H/c-Si interface potential as a function of c-Si depletion width in each sample. By application of Poisson’s equation, we find that the a-Si1−xCx:H/c-Si conduction band offset ΔEc. increases from 0.00 to 0.10 eV as x increases from 0.00 to 0.26. Second, while under reverse-bias at low temperature, we optically pulsed each sample with c-Si band-gap light to create trapped holes at the a-Si1−xCx:H/c-Si valence band offset ΔEV. By noting the threshold for the subsequent optical release of these trapped holes by sub-band gap light, we found that ΔEV increases from 0.67 to ≥0.83 eV as x increases from 0.00 to 0.26.

Temperature and bias dependence of hydrogenated amorphous silicon – crystalline silicon heterojunction capacitance: the link to band bending and band offsets

2014 ◽  
Vol 92 (7/8) ◽  
pp. 690-695 ◽  
Author(s):  
O. Maslova ◽  
A. Brézard-Oudot ◽  
M.E. Gueunier-Farret ◽  
J. Alvarez ◽  
W. Favre ◽  
...  
Keyword(s):  
Temperature Dependence ◽  
Amorphous Silicon ◽  
Crystalline Silicon ◽  
Inversion Layer ◽  
Hydrogenated Amorphous Silicon ◽  
Analytical Calculation ◽  
Diffusion Potential ◽  
Band Offsets ◽  
Strong Inversion ◽  
Hydrogenated Amorphous

The temperature dependence of the capacitance–voltage data (C–V–T) of very high efficiency silicon heterojunction solar cells in a wide temperature range, up to 400 K, is analyzed. We show that the temperature dependence of the capacitance exhibits an anomalously large increase with temperature that cannot be explained under the usual depletion approximation. Using the complete analytical calculation of the capacitance, where the contribution of both types of carriers is taken into account, this large increase of capacitance with temperature of p-type hydrogenated amorphous silicon – n-type crystalline silicon ((p) a-Si:H – (n) c-Si) heterojunctions observed experimentally is reproduced. This increase of the capacitance is due to a strong inversion layer at the c-Si surface, which is promoted as the temperature increases. Further we show that the temperature dependence of the 1/C2 versus applied reverse voltage (Va) plot is as well strongly affected by the strong inversion layer at the c-Si surface. Consequently, the intercept of the linear extrapolation of 1/C2 versus Va with the voltage axis (Vint) differs significantly from the total diffusion potential predicted by depletion capacitance theory. These underestimated values of the total diffusion potential can consequently lead to erroneous estimation of the band offsets. The temperature dependence of Vint is considerably enhanced for the case of the full analytical calculation when compared with the depletion approximation approach. These data, obtained directly on the final solar cell device, thus confirm the existence of a surface strong inversion layer that was previously revealed by measurements performed by other techniques on dedicated or precursor devices, allowing one to get information on the band diagram and the heterointerface.

scholarly journals High quality crystalline silicon surface passivation by combined intrinsic and n-type hydrogenated amorphous silicon

2011 ◽  
Vol 99 (20) ◽  
pp. 203503 ◽  
Author(s):  
Jan-Willem A. Schüttauf ◽  
Karine H. M. van der Werf ◽  
Inge M. Kielen ◽  
Wilfried G. J. H. M. van Sark ◽  
Jatindra K. Rath ◽  
...  
Keyword(s):  
Amorphous Silicon ◽  
Silicon Surface ◽  
Surface Passivation ◽  
Crystalline Silicon ◽  
Hydrogenated Amorphous Silicon ◽  
High Quality ◽  
Hydrogenated Amorphous ◽  
Silicon Surface Passivation

Hall-Effect and Sign Properties in Hydrogenated Amorphous and Disordered Crystalline Silicon

1996 ◽  
Vol 420 ◽  
Author(s):  
C. E. Nebel ◽  
M. Rother ◽  
C. Summonte ◽  
M. Heintze ◽  
M. Stutzmann
Keyword(s):  
Hall Effect ◽  
Amorphous Silicon ◽  
Volume Fraction ◽  
Crystalline Silicon ◽  
Hydrogenated Amorphous Silicon ◽  
Small Volume Fraction ◽  
Phosphorus Doped ◽  
Hydrogenated Amorphous ◽  
Defect Densities ◽  
Very High

AbstractHall experiments on a series of microcrystalline, microcrystalline-amorphous, amorphous and crystalline silicon samples with varying defect densities are presented and discussed. Normal Hall effect signatures on boron and phosphorus doped hydrogenated amorphous silicon are detected. We interpret these results to be due to a small volume fraction of nanocrystalline Si, which falls below the detection limits of Raman experiments. Hydrogenated amorphous silicon, prepared under conditions far away from microcrystalline growth, shows the known double sign anomaly, Sign reversals in c-Si, where the disorder is increased by Si implantation up to very high levels, could not be detected.

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