In situ growth rate measurement and nucleation enhancement for microwave plasma CVD of diamond

1992 ◽  
Vol 7 (2) ◽  
pp. 257-260 ◽  
Author(s):  
B.R. Stoner ◽  
B.E. Williams ◽  
S.D. Wolter ◽  
K. Nishimura ◽  
J.T. Glass

Laser reflection interferometry (LRI) has been shown to be a useful in situ technique for measuring growth rate of diamond during microwave plasma chemical vapor deposition (MPCVD). Current alternatives to LRI usually involve ex situ analysis such as cross-sectional SEM or profilometry. The ability to measure the growth rate in ‘real-time’ has allowed the variation of processing parameters during a single deposition and thus the extraction of much more information in a fraction of the time. In situ monitoring of growth processes also makes it possible to perform closed loop process control with better reproducibility and quality control. Unfortunately, LRI requires a relatively smooth surface to avoid surface scattering and the commensurate drop in reflected intensity. This problem was remedied by greatly enhancing the diamond particle nucleation via the deposition of an intermediate carbon layer using substrate biasing. When an unscratched silicon wafer is pretreated by biasing negatively relative to ground while in a methane-hydrogen plasma, nucleation densities much higher than those achieved on scratched silicon wafers are obtained. The enhanced nucleation allows a complete film composed of small grains to form in a relatively short time, resulting in a much smoother surface than is obtained from a film grown at lower nucleation densities.

1991 ◽  
Vol 235 ◽  
Author(s):  
Yung-Jen Lin ◽  
Ming-Deng Shieh ◽  
Chiapying Lee ◽  
Tri-Rung Yew

ABSTRACTSilicon epitaxial growth on silicon wafers were investigated by using plasma enhanced chemical vapor deposition from SiH4/He/H2. The epitaxial layers were growm at temperatures of 350°C or lower. The base pressure of the chamber was greater than 2 × 10−5 Torr. Prior to epitaxial growth, the wafer was in-situ cleaned by H2 baking for 30 min. The epi/substrate interface and epitaxial layers were observed by cross-sectional transmission electron microscopy (XTEM). Finally, the influence of the ex-situ and in-situ cleaning processes on the qualities of the interface and epitaxial layers was discussed in detail.


1991 ◽  
Vol 236 ◽  
Author(s):  
Yung-Jen Lin ◽  
Ming-Deng Shieh ◽  
Chiapying Lee ◽  
Tri-Rung Yew

AbstractSilicon epitaxial growth on silicon wafers were investigated by using plasma enhanced chemical vapor deposition from SiH4/He/H2. The epitaxial layers were growm at temperatures of 350°C or lower. The base pressure of the chamber was greater than 2 × 10−5 Torr. Prior to epitaxial growth, the wafer was in-situ cleaned by H2 baking for 30 min. The epi/substrate interface and epitaxial layers were observed by cross-sectional transmission electron microscopy (XTEM). Finally, the influence of the ex-situ and in-situ cleaning processes on the qualities of the interface and epitaxial layers was discussed in detail.


2007 ◽  
Vol 336-338 ◽  
pp. 1718-1721 ◽  
Author(s):  
Xiao Ming Liao ◽  
Jun Guo Ran ◽  
Li Gou ◽  
Jin Zhang ◽  
Bao Hui Su ◽  
...  

Due to some inferior performance of Chemical Vapor Deposition (CVD) diamond dosimeters, their applications are somewhat limited. The quality of diamond films was improved using Microwave Plasma CVD (MWPCVD) by the modified processes such as cyclic deposition and in-situ plasma post-treatment. The simple radiation dosimeters were fabricated in a sandwich configuration. Influence of purity and orientation of the diamond films on the sensitivity of the dosimeters was studied. The results indicate that the radiation dosimeters have high sensitivity to X-ray and the response of the devices is linear with the X-ray flux. The higher the purity of films is, the higher the resistivity and sensitivity are. The dosimeter based on [100] film has higher sensitivity than that based on [111] film. The dosimeter based on films prepared by cyclic deposition has higher sensitivity than that based on films prepared by the conventional deposition. The characterization of the response to X-ray also shows that in-situ oxygen plasma post-treatment leads to the higher sensitivity of dosimeters compared with in-situ nitrogen, hydrogen plasma post-treatments.


1997 ◽  
Vol 502 ◽  
Author(s):  
F. Shahedipour ◽  
S. Zhu ◽  
H. W. White

ABSTRACTIn situ Fourier Transform Infrared Reflection Absorption Spectroscopy (FTIRRAS) has been used to study the adsorbed plasma species on sapphire substrate throughout the nucleation and deposition stages under diamond deposition conditions. The focus of this work has been on one of the most fundamental questions in the area of diamond film synthesis that concerns the gas species (precursors) responsible for diamond nucleation and growth especially on foreign substrates. It is experimentally shown here that the most probable precursor for diamond nucleation in methane-hydrogen plasma are methyl radicals.Diamond deposition on randomly oriented sapphire substrates has been successfully achieved under low pressure- low temperature deposition conditions using an electron cyclotron resonance microwave plasma assisted chemical vapor deposition (ECR-PACVD) system. The deposited thin films were characterized by Raman spectroscopy, and scanning electron microscopy.


1994 ◽  
Vol 299 ◽  
Author(s):  
Patricia B. Smith

AbstractDry passivation of HgCdTe with ZnS or CdTe using physical or chemical vapor deposition can be improved by incorporating an in situ plasma cleanup of the HgCdTe surface prior to the deposition. Contamination at the HgCdTe/ dielectric interface from ambient oxide and hydrocarbon residues may lead to fixed charge in capacitor or diode device structures. In addition, the oxides of HgCdTe are known to be thermally unstable. Removal of the surface contamination layer is advantageous for producing a consistent and electrically reliable interface. We describe the interaction of a remotely generated H2 or H2/Ar plasma (2.45 GHz, 600W) with HgCdTe, using ex-situ and in-situ ellipsometry, and atomic force microscopy. This work represents the first effort to characterize a low damage HgCdTe surface cleanup process which is compatible with vacuum in-situ passivation.


1997 ◽  
Vol 470 ◽  
Author(s):  
Y. Z. Hu ◽  
S. P. Tay ◽  
Y. Wasserman ◽  
C. Y. Zhao ◽  
E. A. Irene

ABSTRACTA comparison of SiH4 and Si2H6 chemical vapor deposition kinetics was performed in a rapid thermal processing (RTP) system at temperatures between 600 and 800 °C and reactant gas pressures between 1 and 25 mTorr. Quantitative assessment of the nucleation parameters and the microstructures of the deposited polycrystalline Si (poly-Si) films on SiO2 have been determined using in situ real time single wavelength and spectroscopie ellipsometry. In addition to ellipsometry, atomic force microscopy and cross-sectional transmission electron microscopy were used ex situ to observe the nucleation stage and the microstructures of the poly-Si films. In the present study we compare the nucleation, poly-Si film microstructure and surface roughness using SiH4 and Si2H6 in the RTP system and show that under the same processing conditions the saturation nuclei density (1010 cm−2) for Si2H6 is about 6 times higher than that for SiH4 and the poly-Si films from Si2H6 are smoother and have better columnar structure than those from SiH4.A particularly important parameter for selective epitaxial depositions is the time for nuclei to form, i.e. the incubation time. An operational incubation time were determined from the real time ellipsometric measurements and confirmed by AFM. The incubation times for using SiH4 and Si2H6 are different, but they show similar activation energies of about Einc = 1 eV in the 600–800 °C range. A formula of incubation time tinc was obtained and expressed.


Author(s):  
Hyoung H. Kang ◽  
Michael A. Gribelyuk ◽  
Oliver D. Patterson ◽  
Steven B. Herschbein ◽  
Corey Senowitz

Abstract Cross-sectional style transmission electron microscopy (TEM) sample preparation techniques by DualBeam (SEM/FIB) systems are widely used in both laboratory and manufacturing lines with either in-situ or ex-situ lift out methods. By contrast, however, the plan view TEM sample has only been prepared in the laboratory environment, and only after breaking the wafer. This paper introduces a novel methodology for in-line, plan view TEM sample preparation at the 300mm wafer level that does not require breaking the wafer. It also presents the benefit of the technique on electrically short defects. The methodology of thin lamella TEM sample preparation for plan view work in two different tool configurations is also presented. The detailed procedure of thin lamella sample preparation is also described. In-line, full wafer plan view (S)TEM provides a quick turn around solution for defect analysis in the manufacturing line.


1994 ◽  
Vol 345 ◽  
Author(s):  
T. Kretz ◽  
D. Pribat ◽  
P. Legagneux ◽  
F. Plais ◽  
O. Huet ◽  
...  

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.


Sign in / Sign up

Export Citation Format

Share Document