SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE

To suppress an influence on characteristics due to a metal film constituting a junction layer in a semiconductor device including a plurality of substrates joined via the junction layer.SOLUTION: A semiconductor device 10 includes a first substrate 20 including a semiconductor element, a second substrate 30 joined to the first substrate and made of a material having a higher thermal conductivity than that of the first substrate, and a junction layer 40 provided between the first substrate and the second substrate. The junction layer includes an oxide film 41 provided on at least one side of the first substrate and the second substrate, and a metal film 42 provided in contact with the oxide film and containing oxygen and aluminum. An oxygen content in the metal film gradually changes in a thickness direction of the metal film, and goes higher as the metal film approaches the oxide film.SELECTED DRAWING: Figure 1 【課題】接合層を介して接合された複数の基板を有する半導体装置において、接合層を構成する金属膜による特性への影響を抑制する。【解決手段】半導体装置１０は、半導体素子を有する第１の基板２０と、第１の基板に接合され、第１の基板よりも熱伝導率が高い材料からなる第２の基板３０と、第１の基板と第２の基板との間に設けられた接合層４０と、を含む。接合層は、第１の基板及び第２の基板の少なくとも一方の側に設けられた酸化膜４１と、酸化膜に接して設けられた酸素及びアルミニウムを含む金属膜４２と、を含む。金属膜における酸素含有率が、金属膜の厚さ方向に沿って漸次変化しており、酸化膜に近い程、酸素含有率が高い。【選択図】図１