| 摘要 |
PURPOSE:To prevent the electric characteristics of a contacting hole from deteriorating by forming a high melting point metal or its metal silicide compound in the hole after forming the hole, then reflowing a thin glass film to form a tapered hole to evaporate B and P from BPSG when BPSG reflows, thereby eliminating the adherence of it to the hole. CONSTITUTION:After a contacting hole 8 is opened, a high melting point metal 12 such as TiW is formed on the entire surface, and then heat treated at low temperature. Thus, so-called alloys 13 of silicide TiSi and WSi is produced by the reactions of Ti of TiW and Si, and W and Si of the portion contacted with the Si in the hole. Then, only TiW 12 is removed by H2O2 solution, and the layer 13 remains only in the hole. Thereafter, BPSG reflows at high temperature, a taper is formed in the hole 8, and aluminum electrode wirings 11 are formed. The hole 8 is covered with TiSi/WSi, and B, P impurities of BPSG are not directly contacted with the Si of the substrate. TiSi/WSi act as diffusion stopping layer of B, P to prevent the contacting resistance of the hole from being deteriorated.
|
