Low resistance Ti Ohmic contacts to 4H-SiC by reducing barrier heights without high temperature annealing

作者：Huang, Lingqin^*; Liu, Bingbing; Zhu, Qiaozhi; Chen, Suhua; Gao, Mingchao; Qin, Fuwen; Wang, Dejun

来源：Applied Physics Letters, 2012, 100(26): 263503.

DOI：10.1063/1.4730435

• SCHOTTKY-BARRIER
• PASSIVATION
• EXCELLENT
• MECHANISM
• SURFACES
• TITANIUM
• NI

Ti Ohmic contacts to relatively highly doped (1 x 10(18) cm(-3)) n-type 4H-SiC have been produced, without high temperature annealing, by means of low temperature electronic cyclotron resonance microwave hydrogen plasma pre-treatment (HPT) of the SiC surface. The as-deposited Ti/4H-SiC contacts show Ohmic properties, and the specific contact resistance obtained is as low as 2.07 x 10(-4) Omega.cm(2) after annealing at low temperatures (400 degrees C). This is achieved by low barrier height at Ti/SiC interface, which could be attributed to decrease of surface states density by the HPT releasing Fermi level pinning, and to band-gap narrowing, image-force, and thermionic-field emission at high doping.

• 出版日期2012-6-25
• 单位大连理工大学