Preparation and Optical Properties of Ultrathin Silicon Films

1994 ◽  
Vol 358 ◽  
Author(s):  
R. W. Collins ◽  
Hien V. Nguyen ◽  
Ilsin An ◽  
Yiwei Lu ◽  
M. Wakagi
Keyword(s):  
Vapor Deposition ◽  
Atomic Hydrogen ◽  
Quantum Confinement ◽  
Cluster Size ◽  
Crystalline Silicon ◽  
Chemical Vapor ◽  
Mean Free Path ◽  
Hydrogen Etching ◽  
Electron Mean Free Path

ABSTRACTUltrathin crystalline silicon (c-Si) and amorphous silicon (a-Si:H) films have been prepared using plasma-enhanced chemical vapor deposition (PECVD) and atomic hydrogen etching methods. The complex dielectric functions (2 < hv < 4.5 eV) of films consisting of isolated clusters have been measured in situ and in real time using spectroscopic ellipsometry. For 12 Å c-Si cluster films, a sharp absorption onset is observed near 3 eV that blue-shifts with decreasing thickness, in consistency with the quantum confinement of electrons. A much broader absorption onset, observed for ∼13 Å a-Si:H cluster films near 2 eV, is attributed to an electron mean free path that is less than the cluster size, which limits the appearance of confinement effects.

Optical Properties and Structure of Microcrystalline Silicon

1992 ◽  
Vol 258 ◽  
Author(s):  
Hien V. Nguyen ◽  
Ilsin An ◽  
Youming Li ◽  
C.R. Wronski ◽  
R.W. Collins
Keyword(s):  
Optical Properties ◽  
Vapor Deposition ◽  
Geometric Model ◽  
Chemical Vapor ◽  
Mean Free Path ◽  
Microcrystalline Silicon ◽  
Dominant Effect ◽  
Si Films ◽  
Electron Mean Free Path ◽  
Classical Size

ABSTRACTThe optical properties of thin film microcrystalline silicon (μc-Si:H) prepared by plasma-enhanced chemical vapor deposition (PECVD) have been studied by real time spectroscopie ellipsometry in the nucleation regime as isolated crystalline particles increase in size. A simple geometric model of nucleation allows us to remove the dominant effect of voids and extract the dielectric functions of the crystallites themselves. We find that the results can be understood in terms of a classical size effect whereby limitations on the electron mean free path by scattering at crystallite surfaces control the absorption onset from 2.0 to 3.0 eV. Finally, we describe how well-ordered, continuous 15 Å c-Si films can be prepared on metal substrates.

In situ study of electron beam-induced chemical vapor deposition of Au in an environmental TEM

1995 ◽  
Vol 53 ◽  
pp. 256-257
Author(s):  
J. Drucker ◽  
R. Sharma ◽  
J. Kouvetakis ◽  
K.H.J. Weiss
Keyword(s):  
Electron Beam ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Quantum Effect ◽  
Line Drawing ◽  
Chemical Vapor ◽  
Environmental Cell ◽  
Engineering Changes ◽  
Kinetics Of

Patterning of metals is a key element in the fabrication of integrated microelectronics. For circuit repair and engineering changes constructive lithography, writing techniques, based on electron, ion or photon beam-induced decomposition of precursor molecule and its deposition on top of a structure have gained wide acceptance Recently, scanning probe techniques have been used for line drawing and wire growth of W on a silicon substrate for quantum effect devices. The kinetics of electron beam induced W deposition from WF6 gas has been studied by adsorbing the gas on SiO2 surface and measuring the growth in a TEM for various exposure times. Our environmental cell allows us to control not only electron exposure time but also the gas pressure flow and the temperature. We have studied the growth kinetics of Au Chemical vapor deposition (CVD), in situ, at different temperatures with/without the electron beam on highly clean Si surfaces in an environmental cell fitted inside a TEM column.

In Situ Phosphorus-Doped Poly-Si by Low Pressure Chemical Vapor Deposition for Passivating Contacts

2020 ◽  
Author(s):  
Meric Firat ◽  
Hariharsudan Sivaramakrishnan Radhakrishnan ◽  
Maria Recaman Payo ◽  
Filip Duerinckx ◽  
Rajiv Sharma ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Low Pressure ◽  
Pressure Chemical ◽  
Phosphorus Doped

Deposition and Crystallisation Behaviour of Amorphous Silicon Thin Films Obtained by Pyrolysis of Disilane Gas at Very Low Pressure

1994 ◽  
Vol 345 ◽  
Author(s):  
T. Kretz ◽  
D. Pribat ◽  
P. Legagneux ◽  
F. Plais ◽  
O. Huet ◽  
...  
Keyword(s):  
Activation Energy ◽  
Growth Rate ◽  
Amorphous Silicon ◽  
Vapor Deposition ◽  
Electrical Conductance ◽  
Chemical Vapor ◽  
Crystalline Fraction ◽  
Silicon Thin Films ◽  
Crystallisation Behaviour

AbstractHigh purity amorphous silicon layers were obtained by ultrahigh vacuum (millitorr range) chemical vapor deposition (UHVCVD) from disilane gas. The crystalline fraction of the films was monitored by in situ electrical conductance measurements performed during isothermal annealings. The experimental conductance curves were fitted with an analytical expression, from which the characteristic crystallisation time, tc, was extracted. Using the activation energy for the growth rate extracted from our previous work, we were able to determine the activation energy for the nucleation rate for the analysed-films. For the films including small crystallites we have obtained En ∼ 2.8 eV, compared to En ∼ 3.7 eV for the completely amorphous ones.

The SiNx films process research by plasma-enhanced chemical vapor deposition in crystalline silicon solar cells

2017 ◽  
Vol 31 (16-19) ◽  
pp. 1744101 ◽  
Author(s):  
Bitao Chen ◽  
Yingke Zhang ◽  
Qiuping Ouyang ◽  
Fei Chen ◽  
Xinghua Zhan ◽  
...  
Keyword(s):  
Thin Film ◽  
Chemical Vapor Deposition ◽  
Solar Cell ◽  
Vapor Deposition ◽  
Gas Flow ◽  
Silicon Solar Cell ◽  
Crystalline Silicon ◽  
Chemical Vapor ◽  
Double Layers ◽  
Crystalline Silicon Solar Cell

SiNx thin film has been widely used in crystalline silicon solar cell production because of the good anti-reflection and passivation effect. We can effectively optimize the cells performance by plasma-enhanced chemical vapor deposition (PECVD) method to change deposition conditions such as temperature, gas flow ratio, etc. In this paper, we deposit a new layer of SiNx thin film on the basis of double-layers process. By changing the process parameters, the compactness of thin films is improved effectively. The NH3passivation technology is augmented in a creative way, which improves the minority carrier lifetime. In sight of this, a significant increase is generated in the photoelectric performance of crystalline silicon solar cell.

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