[14a-D419-1~12] 6.1 Ferroelectric thin films

[14a-D419-7] Ferroelectricity of GaN and Sc-doped GaN Thin Films Prepared by Sputtering Method

〇Masato Uehara¹, Shinnosuke Yasuoka², Takao Shimizu², Hirosshi Yamada¹, Morito Akiyama¹, Hiroshi Funakubo² (1.AIST, 2.Tokyo Tech.)

Keywords:ferroelectricity, nitride, sputtering

Wurtzite AlN and GaN have a polarity with c-axis, and they are applied as a piezo material in the MEMS devices. It is known that these materials is softened by Sc doping and the piezoelectric coefficient d33 is significantly increased. Recently, Fichtner et. al reported that the Sc-doped AlN by sputtering exhibited a ferroelectricity. Because the change of properties by Sc-doping in GaN is similar with that of AlN, the ferroelectricity is expectable in also GaN. In this paper, we prepared GaN and Sc-doped GaN films by sputtering and investigated the ferroelectricity.