1989 Fiscal Year Final Research Report Summary
InP Surface Control with Photo-Assisted CVD and Its Application to Devices
Project/Area Number |
63550239
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Research Category |
Grant-in-Aid for General Scientific Research (C)
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Allocation Type | Single-year Grants |
Research Field |
電子材料工学
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Research Institution | Aoyama Gakuin University |
Principal Investigator |
KUNIOKA Akio AOYAMA GAKUIN UNIVERSITY, College of Science & Engineering, Professor, 理工学部, 教授 (50082756)
|
Co-Investigator(Kenkyū-buntansha) |
NAKADA Tokio AOYAMA GAKUIN UNIVERSITY, College of Science & Engineering, Senior Assistant., 理工学部, 主管助手 (90082825)
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Project Period (FY) |
1988 – 1989
|
Keywords | Photo-CVD / Silicon Nitride / Indium Phosphide / MIS Structure / Interface State Density |
Research Abstract |
The high mobility and saturation velocity of electrons in InP have made it a very attractive material for MISFET's. The surface of the InP has been passified by the deposition of amorphous dielectrics. Silicon nitride(SiN) is useful as a diffusion barrier in the gates of FET and in capacitors, as a capping layer during annealing and as an insulator with a high dielectric constant. The dissociation of the phosphorus from the InP surface during the deposition of gate insulators is a serious drawback in device fabrication. In order to exploit the advantage of InP MISFET fabrication, it is necessary to minimize the density of states at the interface between the insulator and the InP by using a low deposition temperature and reducing surface damage. Photoasosted chemical vapor deposition(photo-CVD) technique makes it possible to form the insulating layer at low temperatures without surface damage. The properties of the interface between the photo-CVD SiN film and the InP surface were evaluated by means of C-V measurements on MIS diodes. A high NH_3/SiH_4 flow rate ratio produced a low interface state density. A high substrate temperature also had the same effect. In both cases, some oxygen was detected in the SiN layer by XPS spectroscopy. The effect of oxygen seems to become more pronounced because of the low interface state density. In order to investigate this phenomena, the oxygen was added to the source gas. SiN layers added to oxygen resulted in a decrease in the interface state density, and leads to an increase in the deposition rate and the BHF etching rate.
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Research Products
(6 results)