The Influences of Thermal and Surface Processes on Schottky Barrier Height

• Main Authors: Feng-Ling Shiau, 蕭鳳玲
• Other Authors: Mau-Phon Houng, Yeong-Her Wang
• Format: Others
• Language: en_US
• Published: 1995
• Online Access: http://ndltd.ncl.edu.tw/handle/70507627737928785291

碩士 === 國立成功大學 === 電機工程研究所 === 83 === The effects of thermal process and surface passivation on Schottky barrier height of several kinds of metal-n/GaAs were investigated.Using MBE, n-GaAs buffer layer was grown between N- type GaAs substrate and metal to improve the performance of schottky barrier height. The conceration of this buffer layer can''t be so high to form ohmic contact.Three different concentrations 1E16 cm-3,5*10E16 cm-3 and 1*10E17cm-3 are discussed. We deposite several kinds of metal as Ag, Pt, and Al on buffer layer by evaporation method and compare the performance of hat the property of Schottky contact of Al is worse than that of Ag due to the large chemical activity of Al in our experiement although the Al contact is so far the best in the presented document. Next,the Schottky Diode is annealed under different condition,ie, 300C/5min, 400C/1min, 550C/20s. We observe that the barrier height is enhanced after annealing because the formation of the interfacial stable compound (Ga,Al) As, which has been examined by scanning Auger microscopy and X- ray.And we can get an optimum barrier height at 400C/1min. But the Ag contact opposites this condition. At last, the interface stable density effects on the electrical properties was studied. Schottky barriers have been prepared on the sulfide- treated GaAs. We found that the interface trap density was reduced by this passivation and the barriers are more sensitive to the metal work function.