Electron Cyclotron Resonance Plasma Etching of n-SiC and Evaluation of Ni/n-SiC Contacts by Current Noise Measurements

• Published in: Japanese Journal of Applied Physics 2001, Vol.40 (6R), p.3979-3984
• Main Authors: Nobuhisa Tanuma, Nobuhisa Tanuma, Satoshi Yasukawa, Satoshi Yasukawa, Saburo Yokokura, Saburo Yokokura, Sumihisa Hashiguchi, Sumihisa Hashiguchi, Josef Sikula, Josef Sikula, Toshiaki Matsui, Toshiaki Matsui, Munecazu Tacano, Munecazu Tacano
• Format: Article
• Language: English
• ISSN: 0021-4922; 1347-4065
• DOI: 10.1143/JJAP.40.3979

The Si surface of n-SiC is etched by an Ar electron cyclotron resonance plasma in order to smooth the as-received substrates. Low-frequency current noise characteristics of Ohmic contacts of the wide-band-gap semiconductor n-SiC are investigated. Ohmic contacts with a diameter of 200 µm have a minimum Ohmic contact resistance of the order of 10 -4 Ω·cm 2 at an alloying temperature of 1000°C for 30 min. These low resistance Ohmic contacts show typical 1/ f current noise characteristics that increase with the square of the sample current I 2 . A sample with a higher contact resistance exhibits, however, current noise power increase with increasing sample current I . The relevant total electron number between the electrodes of the bulk substrate is estimated from the resistance and by finite element method simulation, from which the Hooge parameter α H is estimated to be approximately 40.