低誘電率（Low-k）熱酸化陽極化成Siの作製と誘電特性の評価

摘要

次世代LSI層間絶縁膜として期待されているLow-k薄膜材料を，陽極化成により多孔質化した陽極化成Siを熱酸化することで作製した.試料は，低抵抗n型Si単緬晶を原材料として，陽極化成電流密度の変化で多孔度を変えた陽極化成Siを作製し，それを1000℃の酸素ガ大中で熱酸化を行うことで作製した.試料の誘電率は，5×10~2～5×10~6 Hzの周波数の範囲で変化は見られない.また，電流密度100mA/cm~2で作製した多孔度73％の陽極化成Siを酸化した試料の誘電率は，k＝3.0の値が得られた.%Low-k dielectric thin film material have been successfully prepared by thermal oxidization using anodized silicon. Anodized silicon layers were prepared using low resistivity n-type silicon single crystal. The anodized silicon layers which porosity was varied anodized current density were oxygenated in the oxygen gas at 1,000 ℃. There is no significant change of the dielectric constant in the frequency range of 5 × 10~2 ~ 5 × 10~6 Hz. The dielectric constant for the samples with a value of the porosity as 73% by anodized current density as 100 mA/cm~2 is typically k = 3.0.