[15a-B9-1~6] 13.3 Insulator technology

[15a-B9-3] Annealing effect on electric characteristics of atomic-layer-deposition Al₂O₃ films

〇Atsushi Hiraiwa^1,3, Daisuke Matsumura², Satoshi Okubo², Hiroshi Kawarada^1,2 (1.RONL, Waseda Univ., 2.FSE, Waseda Univ., 3.IMaSS, Nagoya Univ.)

Keywords:Al2O3, electric current, anneal

We report an annealing effect on electric characteristics of Al₂O₃ films formed at 100ºC using atomic layer deposition with H₂O oxidant. The negative-bias leakage current of the Al₂O₃ films annealed at above 300ºC is smaller than the current of Al₂O₃ films formed at the same temperature as the annealing temperature. On the other hand, irrespective of the annealing temperature, the positive-bias leakage current of the annealed films is smaller than the current of the films formed at the same temperature as the annealing temperature. Given that the dielectric constant of the annealed films slightly decreases with an increasing annealing temperature, the aforementioned reduction of leakage currents does not lead to the improvement of MISFET performance. To reduce the leakage current, the technology for reducing positive charges and dipoles near Al₂O₃/semiconductor interface is open to further investigations.