Semiconductor Energy Laboratory Co., Ltd.

Hyogo Prefecture

Japan Society for the Promotion of Science

Hideki Tsuya

Kazuya Hanaoka

Masaharu Nagai

Yoshihiro Komatsu

Seigo Kishino

The method of one embodiment of the present invention includes: a first step of irradiating a bond substrate with ions to form an embrittlement region in the bond substrate; a second step of bonding the bond substrate to a base substrate with an insulating layer therebetween; a third step of splitting the bond substrate at the embrittlement region to form a semiconductor layer over the base substrate with the insulating layer therebetween; and a fourth step of subjecting the bond substrate split at the embrittlement region to a first heat treatment in an argon atmosphere and then a second heat treatment in an atmosphere of a mixture of oxygen and nitrogen to form a reprocessed bond substrate. The reprocessed bond substrate is used again as a bond substrate in the first step.

Method of manufacturing SOI substrate

An insulating layer is formed over a surface of a semiconductor wafer to be the bond substrate and irradiation with accelerated ions is performed, so that an embrittlement region is formed inside the wafer. Next, this semiconductor wafer and a base substrate such as a glass substrate or a semiconductor wafer are attached to each other. Then, the semiconductor wafer is divided at the embrittlement region by heat treatment, whereby an SOI substrate is manufactured in which a semiconductor layer is provided over the base substrate with the insulating layer interposed therebetween. Before this SOI substrate is manufactured, heat treatment is performed on the semiconductor wafer at 1100&#xb0; C. or higher under a non-oxidizing atmosphere such as an argon gas atmosphere or a mixed atmosphere of an oxygen gas and a nitrogen gas.

Method for manufacturing SOI substrate

On a silicon layer of an SOI wafer is defined a semiconductor device-forming region to form semiconductor devices thereon and an insulating region to electrically insulate the semiconductor device-forming region. Then, a mask layer is formed of nitride by means of photolithography so as to cover the semiconductor device-forming region. Then, an impurities-removing layer is formed by means of well known technique so as to cover the mask layer and embed the gaps between the adjacent masks of the mask layer. The impurities of the silicon layer of the SOI wafer are absorbed and removed by the distorted layer, the grain boundaries and the lattice defects of the impurities-removing layer.

Growing community of inventors

Yokohama, Japan

Hideki Tsuya