Role of Hydrogen Plasma during Growth of Hydrogenated Microcrystalline Silicon: In Situ UV-Visible and Infrared Ellipsometry Study

1994 ◽  
Vol 33 (Part 1, No. 10) ◽  
pp. 5590-5598 ◽  
Author(s):  
Hajime Shirai ◽  
Bernard Drévillon ◽  
Isamu Shimizu
2021 ◽  
Author(s):  
Om Kumar Prasad ◽  
Srikant Kumar Mohanty ◽  
ChienHung Wu ◽  
Tsung Ying Yu ◽  
K-M Chang

1998 ◽  
Vol 507 ◽  
Author(s):  
S. Hamma ◽  
D. Colliquet ◽  
P. Rocai Cabarrocas

ABSTRACTMicrocrystalline silicon films were deposited on corning glass substrates both by the standard hydrogen dilution and the layer-by-layer (LBL) technique. In-situ UV-visible spectroscopic ellipsometry measurements were performed to analyze the evolution of the composition of the films.The change of the hydrogen plasma conditions by increasing the pressure in the LBL process leads to a faster kinetic of crystallization and to an increase of the deposition rate by a factor of two. The increase of the pressure and the decrease of the inter-electrode distance allowed to increase the deposition rate from 0.26 to 3 Å/s in the hydrogen dilution technique. Interestingly enough, the crystalline fraction of the films remains higher than 50%. However, as the deposition rate increases the growth process results in a slower kinetic of crystallization with a long range evolution of the film composition (up to 0.5 νm).


1997 ◽  
Vol 71 (23) ◽  
pp. 3403-3405 ◽  
Author(s):  
K. Saitoh ◽  
M. Kondo ◽  
M. Fukawa ◽  
T. Nishimiya ◽  
A. Matsuda ◽  
...  

1998 ◽  
Vol 507 ◽  
Author(s):  
S. Hamma ◽  
P. Rocai Cabarrocas

ABSTRACTIn-situ UV-visible ellipsometry and Kelvin probe measurements were performed to study the growth of boron-doped microcrystalline silicon (μc-Si:H) thin films and the band profiling at the p- (μc-Si:H)/i-(a-Si:H) interface. The in-situ UV-visible spectroscopic ellipsometry measurements, combined with dark conductivity measurements, performed at different stages of the growth show that p-type μc-Si:H formation can be achieved for a film thickness below 10 nm. These analyses also reveal that both the optical absorption, and the dark conductivity do not change significantly for a crystalline volume fraction above 50%. Moreover, the contact potential as measured by in- situ Kelvin probe shows a saturation just after the percolation threshold. These results indicate that highly crystallized doped layers are not necessary in device applications. From the Kelvin probe measurements, the potential profile through the p-(μc-Si:H)/ i-(a-Si:H) interface was measured. The microcrystalline silicon p-layers were successfully incorporated in single junction solar cells.


1991 ◽  
Vol 237 ◽  
Author(s):  
N. Blayo ◽  
B. Drevillon

ABSTRACTThe early stages of the growth of plasma deposited amorphous silicon (a-Si:H) and microcrystalline silicon (μc-Si) on glass substrates are investigated by in situ infrared phase modulated ellipsometry (IRPME) in the silicon-hydrogen stretching mode region. μc-Si are prepared by alternating SiH4 and H2 plasmas. New insights on the plasma-surface interactions during the growth of these films are given. During the deposition of the first 20 Å of a-Si:H, the hydrogen is incorporated as SiH2. During the further growth of a-Si:H the SiH2 bonds are located at the film surface inside a very thin hydrogen rich overlayer. During the deposition of the first 10–20 Å of μc-Si, the SiH2 bonds are predominantly removed by the H2 plasma, the material being amorphous. After this selective removal of the SiH2 groups, a transition from amorphous to microcrystalline growm is observed. A systematic hydrogen etching during the further growth of μc-Si is observed.


2006 ◽  
Vol 910 ◽  
Author(s):  
Gye-Hyun Lee ◽  
Jong-Hwan Yoon

AbstractThick microcrystalline silicon (mc-Si:H) films were exposed to atomic hydrogen plasma at substrate temperature of 220°C after deposition. The microstructure of μc-Si:H films after exposure was characterized using Raman back scattering spectroscopy and transmission electron microscopy (TEM). Raman spectra reveal that the intensity near 520 cm−1 significantly increases after hydrogen exposure, indicating an increase of crystallinity in the films. TEM micrographs of μc-Si:H films exposed to atomic hydrogen also show an increase in the size of grains and a growth of crystalline grains ranging from surface to bulk. These results suggest that crystalline grain formation in μc-Si:H films is likely to be caused by chemical annealing.


2003 ◽  
Vol 762 ◽  
Author(s):  
C. Smit ◽  
D.L. Williamson ◽  
M.C.M. van de Sanden ◽  
R.A.C.M.M. van Swaaij

AbstractExpanding thermal plasma CVD (ETP CVD) has been used to deposit thin microcrystalline silicon films. In this study we varied the position at which the silane is injected in the expanding hydrogen plasma: relatively far from the substrate and close to the plasma source, giving a long interaction time of the plasma with the silane, and close to the substrate, resulting in a short interaction time. The material structure is studied extensively. The crystalline fractions as obtained from Raman spectroscopy as well as from X-ray diffraction (XRD) vary from 0 to 67%. The average particle sizes vary from 6 to 17 nm as estimated from the (111) XRD peak using the Scherrer formula. Small angle X-ray scattering (SAXS) and flotation density measurements indicate void volume fractions of about 4 to 6%. When the samples are tilted the SAXS signal is lower than for the untilted case, indicating elongated objects parallel to the growth direction in the films. We show that the material properties are influenced by the position of silane injection in the reactor, indicating a change in the plasma chemistry.


Sign in / Sign up

Export Citation Format

Share Document