Method for manufacturing soi substrate

Abstract

An object is to provide a method for manufacturing an SOI substrate, by which defective bonding can be prevented. An embrittled layer is formed in a region of a semiconductor substrate at a predetermined depth; an insulating layer is formed over the semiconductor substrate; the outer edge of the semiconductor substrate is selectively etched on the insulating layer side to a region at a greater depth than the embrittled layer; and the semiconductor substrate and a substrate having an insulating surface are superposed on each other and bonded to each other with the insulating layer interposed therebetween. The semiconductor substrate is heated to be separated at the embrittled layer while a semiconductor layer is left remaining over the substrate having an insulating surface.

1 . A doping apparatus comprising:
 an ion irradiation mechanism comprising an ion source for generating molecular ions and an acceleration mechanism of the molecular ions;   a substrate holding mechanism comprising a back supporting portion on which a process substrate is placed; and   a control mechanism,   wherein a tilt angle between the process substrate and vertical direction during ion irradiation is held at 10° or larger and is not larger than 90°.   
     
     
         2 . The doping apparatus according to  claim 1 , wherein the molecular ions are hydrogen ions. 
     
     
         3 . The doping apparatus according to  claim 1 , wherein each of the molecular ions comprises three atoms. 
     
     
         4 . The doping apparatus according to  claim 1 , wherein the process substrate is a single crystal silicon substrate. 
     
     
         5 . The doping apparatus according to  claim 1 , wherein an incident angle of each molecular ion is in the range of 80° to 100°. 
     
     
         6 . A doping apparatus comprising:
 a molecular ion irradiation mechanism comprising an ion source for generating molecular ions and an acceleration mechanism of the molecular ions;   a substrate holding mechanism comprising a back supporting portion on which a process substrate is placed with a tilt angle between the process substrate and vertical direction, and   a control mechanism,   wherein the tilt angle is 10° or larger and is not larger than 90°.   
     
     
         7 . The doping apparatus according to  claim 6 , wherein the molecular ions are hydrogen ions. 
     
     
         8 . The doping apparatus according to  claim 6 , wherein each of the molecular ions comprises three atoms. 
     
     
         9 . The doping apparatus according to  claim 6 , wherein the process substrate is a single crystal silicon substrate. 
     
     
         10 . The doping apparatus according to  claim 6 , wherein an incident angle of each molecular ion is in the range of 80° to 100°. 
     
     
         11 . A doping apparatus comprising:
 a molecular ion irradiation mechanism comprising an ion source for generating molecular ions and an acceleration mechanism of the molecular ions;   a substrate holding mechanism by which a process substrate is held with a tilt angle between the process substrate and vertical direction, and   a control mechanism,   wherein the substrate holding mechanism comprising a back supporting portion on which the process substrate is placed, and   wherein the tilt angle is 10° or larger and is not larger than 90°.   
     
     
         12 . The doping apparatus according to  claim 11 , wherein the molecular ions are hydrogen ions. 
     
     
         13 . The doping apparatus according to  claim 11 , wherein each of the molecular ions comprises three atoms. 
     
     
         14 . The doping apparatus according to  claim 11 , wherein the process substrate is a single crystal silicon substrate. 
     
     
         15 . The doping apparatus according to  claim 11 , wherein an incident angle of each molecular ion is in the range of 80° to 100°.