SEMICONDUCTOR DEVICE MANUFACTURING METHOD

• Main Authors: SAKATA JUNICHIRO, YAMAZAKI SHUNPEI, SASAKI TOSHINARI, OHARA HIROKI
• Format: Patent
• Language: English; Japanese
• Published: 13.10.2016
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

PROBLEM TO BE SOLVED: To manufacture and provide a semiconductor device which has a thin film transistor having stable electrical properties, and has high reliability.SOLUTION: A manufacturing method of a semiconductor device having a thin film transistor which includes an oxide semiconductor film as a semiconductor layer including a channel formation region, comprises the steps of: reducing an impurity such as moisture existing in a gate insulation layer before forming an oxide semiconductor film; subsequently performing a heating treatment (heating treatment for dewatering or dehydrogenation) to increase purity of the oxide semiconductor film and reduce moisture and the like as the impurity; then, cooling the oxide semiconductor film in an oxygen atmosphere slowly; and then reducing an impurity such as moisture existing in interfaces between the oxide semiconductor film and films provided above and below the oxide semiconductor film as well as in the gate insulation layer and in the oxide semiconductor film.SELECTED DRAWING: Figure 1 【課題】安定した電気特性を有する薄膜トランジスタを有する、信頼性のよい半導体装置を作製し、提供することを課題の一とする。【解決手段】チャネル形成領域を含む半導体層を酸化物半導体膜とする薄膜トランジスタを有する半導体装置の作製方法において、酸化物半導体膜前にゲート絶縁層内に存在する水分などの不純物を低減した後、酸化物半導体膜の純度を高め、不純物である水分などを低減する加熱処理（脱水化または脱水素化のための加熱処理）を行った後、酸素雰囲気下において徐冷する。ゲート絶縁層中、及び酸化物半導体膜中に加え、上下に接して設けられる膜と酸化物半導体膜の界面に存在する水分などの不純物を低減する。【選択図】図１