Study On The Ohmic Contact For P-type SiC Reliability At High Temperature

Concerning problems on reliability of P-SiC ohmic contact using at high temperature, combining quantum tunneling mechanism of ohmic contact, this paper gives ohmic contact method, in which multiple bed configuration of Al or polysilicon is used to be epitaxial layer of P-SiC. The main results are made in the following aspects:1) First, technique of ohmic contact used on P-SiC is analysed and some key problems of Fermi pinning and so on are discussed; and then how to enhance contacting reliability is summed up through method of two aspects about material and technique.2) The characteristic of SiC,apparatus used in the experiment,specific resistance and methold of reliability testing are introduced in detail respectively, and the measurement of 3C-SiC ohmic contact is used as an example to describe the measuring method of enhancing precision.3) How to form SiC ohmic contact is studied. Firstly form of Fermi pinning effect and eliminating method with technique are introduced; then alloy theory and C-vacancy theory are analysed; finally a new nanometer tunneling formation mechanism is given that is based on quantum mechanics, and the ineffectual reasons are discussed.4) A method that combines radio frequency (RF) plasma with hot filament (HF) chemical vapor deposition (CVD) together has been used to prepare 3C-SiC film; and multiple bed configuration of Al or polysilicon is used to be epitaxial layer of P-SiC.