Abstract: An SOI substrate which has a thick SOI layer is first prepared. Then, the SOI layer is thinned to a target film thickness using as a unit a predetermined thickness not more than that of one lattice. This thinning is performed by repeating a unit thinning step which includes an oxidation step of oxidizing the surface of the SOI layer by the predetermined thickness not more than that of one lattice and a removal step of selectively removing silicon oxide formed by the oxidation. The SOI layer of the SOI substrate is chemically etched by supplying a chemical solution to the SOI layer, and the film thickness of the etched SOI layer is measured. When the measured film thickness of the SOI layer has a predetermined value, a process of chemically etching the SOI layer ends.

Abstract: An SOI substrate which has a thick SOI layer is first prepared. Then, the SOI layer is thinned to a target film thickness using as a unit a predetermined thickness not more than that of one lattice. This thinning is performed by repeating a unit thinning step which includes an oxidation step of oxidizing the surface of the SOI layer by the predetermined thickness not more than that of one lattice and a removal step of selectively removing silicon oxide formed by the oxidation. The SOI layer of the SOI substrate is chemically etched by supplying a chemical solution to the SOI layer, and the film thickness of the etched SOI layer is measured. When the measured film thickness of the SOI layer has a predetermined value, a process of chemically etching the SOI layer ends.

Abstract: This invention provides a method of manufacturing a substrate having a thin buried insulating film. An insulating layer (12) is formed on a single-crystal Si substrate (11). Ions are implanted into the substrate (11) through the insulating layer (12) to form an ion-implanted layer (13). The insulating layer (12) is thinned down to form a thin insulating layer (12a). A thus prepared first substrate is placed on a second substrate (20) to form a bonded substrate stack (30). After that, the bonded substrate stack (30) is split at the ion-implanted layer (13).

Abstract: An SOI substrate which has a thick SOI layer is first prepared. Then, the SOI layer is thinned to a target film thickness using as a unit a predetermined thickness not more than that of one lattice. This thinning is performed by repeating a unit thinning step which includes an oxidation step of oxidizing the surface of the SOI layer by the predetermined thickness not more than that of one lattice and a removal step of selectively removing silicon oxide formed by the oxidation. The SOI layer of the SOI substrate is chemically etched by supplying a chemical solution to the SOI layer, and the film thickness of the etched SOI layer is measured. When the measured film thickness of the SOI layer has a predetermined value, a process of chemically etching the SOI layer ends.

Abstract: This invention provides a method of manufacturing a substrate having a thin buried insulating film. An insulating layer (12) is formed on a single-crystal Si substrate (11). Ions are implanted into the substrate (11) through the insulating layer (12) to form an ion-implanted layer (13). The insulating layer (12) is thinned down to form a thin insulating layer (12a). A thus prepared first substrate is placed on a second substrate (20) to form a bonded substrate stack (30). After that, the bonded substrate stack (30) is split at the ion-implanted layer (13).

Abstract: To lessen the number of steps and reduce cost in the manufacture of high-quality SOI substrate, a process for producing a semiconductor article comprises the steps of forming a porous semiconductor layer at at least one surface of a first substrate, forming a non-porous single-crystal semiconductor layer on the porous semiconductor layer, bonding the first substrate to a second substrate with the former's non-porous single-crystal semiconductor layer facing the latter in contact, to form a bonded structure, and dividing the bonded structure at the porous semiconductor layer, wherein the process further comprises the step of previously forming on the one surface of the first substrate an epitaxial silicon layer in a thickness at least n-times (n≧2) the thickness of the porous semiconductor layer.