[20p-S221-1~17] 13.3 Insulator technology

[20p-S221-4] Electric characteristics of Al₂O₃ films formed at different ALD temperatures

〇Atsushi Hiraiwa¹, Daisuke Matsumura², Hiroshi Kawarada^1,2 (1.Waseda Univ., RONL, 2.Waseda Univ., FSE)

Keywords:Al2O3,gate insulator,ALD

We are developing high-reliability ALD-Al₂O₃ films suitable for gate insulation of wide-bandgap semiconductor devices. Here, we report the electric insulation characteristics of Al₂O₃ films formed at different ALD temperatures. Under the same equivalent oxide field, which determines MISFET performance, the leakage current of Au-gated Al₂O₃ capacitors decreases with ALD temperature and bottoms above 200ºC. Considering that the thermostability of the ALD-Al₂O₃ films further increases with ALD temperature above 200ºC, high-temperature (450ºC) ALD is a good solution to the challenge of forming high-reliability Al₂O₃ gate insulators.