Electrode and wiring structure of semiconductor device

Abstract

Abstract PURPOSE:To avoid the generation of channeling when electrodes and wirings consisting of high-melting-point metals are arranged in a semiconductor device and impurity layers are formed by self-aligning by ion implantation using said electrodes and wirings as a mask by providing an oxide film consisting of the same metal on the metal surface before the ion implantation. CONSTITUTION:A thick SiO2 film 2 for element isolation is formed on a circumferential portion of a p type Si substrate 1 and a thin gate SiO2 film 3 is arranged on the substrate surface surrounded with said SiO2 film 2 and further the whole surface is coated with a film 4 of a high-melting-point metal such as Mo. Next, a mask 5 of a photoresist film is arranged on the substrate followed by etching using CF4 gas including O2 of 20% of leave the film 4 only in the center of surface. After that, the mask 5 is removed and a heat treatment is performed with 400 deg.C in O2 atmosphere to produce an oxide film 6 on a surface of the exposed film 4. Then this film is used as a mask to implant As ions and an implantation region 7 is formed. Thus, the ions enter deeply because atomic configurations of the metallic oxide and the metal are different and channeling is diminished.

Inventors

• 👤 Naoki Yamamoto
• 👤 直樹 山本
• 👤 Seiichi Iwata
• 👤 誠一 岩田
• 👤 Takao Amasawa
• 👤 天沢　敬生

Bibliographic Details