SEMICONDUCTOR DEVICE

• Main Author: KAWAKAMI YASUHIRO
• Format: Patent
• Language: English; Japanese
• Published: 29.03.2018
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

PROBLEM TO BE SOLVED: To provide a semiconductor device which can reduce forward voltage while suppressing reverse leakage current comparable to the conventional semiconductor device; and further, which can reduce fluctuation in reverse leakage current.SOLUTION: A semiconductor device includes a first conductivity type SiC semiconductor layer 6 and a Schottky metal 11 which is composed of molybdenum in contact with a surface of the SiC semiconductor layer and has a thickness of 10 nm-150 nm. The SiC semiconductor layer has a junction part 61 with the Schottky metal, which is flat or has an irregular structure 13 of equal to or less than 5 nm. A manufacturing method of the semiconductor device comprises the steps of: forming on a surface 6A of the first conductivity type SiC semiconductor layer, the Schottky metal; and performing a heat treatment on the Schottky metal in a state where a surface of the Schottky metal is exposed to make the junction part of the SiC semiconductor layer with the Schottky metal flat or have the irregular structure of equal to or less than 5 nm.SELECTED DRAWING: Figure 3 【課題】逆方向リーク電流を従来と同程度に抑えながら、順方向電圧を低減することができ、さらに、逆方向リーク電流のばらつきを小さくすることができる半導体装置を提供する。【解決手段】半導体装置は、第１導電型のＳｉＣ半導体層６と、ＳｉＣ半導体層の表面に接するモリブデンからなり、１０ｎｍ〜１５０ｎｍの厚さを有するショットキーメタル１１とを含む。ＳｉＣ半導体層のショットキーメタルとの接合部６１は、平坦もしくは５ｎｍ以下の凹凸構造１３である。半導体装置の製造方法は、第１導電型のＳｉＣ半導体層の表面６Ａに、前記ショットキーメタルを形成する工程と、ショットキーメタルの表面を露出させた状態でショットキーメタルを熱処理し、ＳｉＣ半導体層のショットキーメタルとの接合部を、平坦もしくは５ｎｍ以下の凹凸構造にする工程とを含む。【選択図】図３