Direct observations of heteroepitaxial diamond on a silicon(110) substrate by microwave plasma chemical vapor deposition
- PDF / 896,954 Bytes
- 9 Pages / 612 x 792 pts (letter) Page_size
- 11 Downloads / 232 Views
MATERIALS RESEARCH
Welcome
Comments
Help
Direct observations of heteroepitaxial diamond on a silicon(110) substrate by microwave plasma chemical vapor deposition C. J. Chen Materials Science Center, Tsin Hua University, Hsinchu, Taiwan 300, Republic of China
L. Chang Division of Engineering and Applied Science, National Science Council, Taipei, Taiwan 10636, Republic of China
T. S. Lin Materials Research Laboratories, Industrial Technology Research Institute, Hsinchu, Taiwan 31015, Republic of China
F. R. Chen Materials Science Center, Tsin Hua University, Hsinchu, Taiwan 300, Republic of China (Received 3 October 1994; accepted 1 October 1995)
Heteroepitaxial diamond has been successfully deposited on a Si(110) substrate by the microwave plasma chemical vapor deposition method. The pretreatment consisted of carburization and bias-enhanced nucleation steps. Cross-sectional transmission electron microscopy reveals that diamond can be in the cube-on-cube epitaxial relationship with the Si substrate. Various orientation relationships between diamond and Si substrates have also been observed, depending on the location where the plasma applied. Near the center of the plasma, twins were rarely observed in cube-on-cube epitaxial regions. Away from the center of the plasma ball, S3 twins are seen first, and then additional S9 and S27 twins occur near the edge of the plasma. In general, defect density in the epitaxial films is less than that observed in polycrystalline ones. No interlayer could be observed between diamond and silicon. In addition, 2H-type hexagonal diamond has also been found, and is in epitaxy with the Si substrate.
I. INTRODUCTION
Diamond has great potential to be used as a semiconductor for high performance electronic devices like silicon in integrated circuits. It would be a great advantage if diamond could be deposited in heteroepitaxy with substrate. Currently, heteroepitaxy of diamond growth by chemical vapor deposition (CVD) has been demonstrated on substrates of cubic BN, cubic SiC, and BeO.1–5 Local epitaxy has been reported on Ni, Cu, Si, and 6H–SiC.6–10 Epitaxial growth of diamond on Si has also been reported by several groups.11–17 To grow heteroepitaxial diamond on Si has some advantages because single crystal Si wafers with extreme low defect density are easily available in large sizes up to 8 in. inexpensively. Approaches for epitaxial deposition of diamond on Si can either go through an epitaxial SiC layer or directly form on Si. Both approaches probably need a high nucleation density to form a continuous film. Without any pretreatment on the substrates, it is difficult for diamond nucleation to occur on the smooth surface. The conventional pretreatment for nucleation enhancement is a mechanical process including scratching or grinding with diamond powders which would be difficult to 1002
http://journals.cambridge.org
J. Mater. Res., Vol. 11, No. 4, Apr 1996
Downloaded: 17 Mar 2015
control the surface roughness in uniformity at submicron scale for nucleation. The bias enhanced
Data Loading...
