Manufacture of soi substrate

Abstract

Abstract PURPOSE:To enable a Si layer to have an impurity concentration required for the formation of an element by a method wherein Si is removed except a p<+> doped layer on a first Si substrate after a the p<+> doped layer on the first Si substrate has been bonded to an insulating layer on a second Si substrate, and a part of the p<+> doped layer is oxidized. CONSTITUTION:A p<+> boron doped layer 2, a SiO2 layer 3, and a BPSG film 4 are provided onto a primary face of a Si substrate 1 to form a first substrate 5. The substrate 5 is bonded to a second substrate 9, composed of an SiO2 film 7 and a BPSG film 8 which are formed on a Si substrate 6, using the films 4 and 8, and then the substrate 5 is removed except the layer 2 to make the bonded substrate a thin layer. Then, the substrate is oxided in a moistened oxygen atmosphere to form a SiO2 film 11. In this process, an SOI(Silicon on Insulator) substrate, provided with a Si layer whose boron concentration is 3-4X10<16>cm<-3> is formed through the suction of boron due to a segregation effect as the boron high concentrated layer 2 grows gradually to be a thin layer by oxidation.

Inventors

• 👤 Kazuo Imai
• 👤 和雄 今井

Bibliographic Details