Patent ID: 11959191
Assignee: SHIN-ETSU HANDOTAI CO., LTD.
Field: Surface technology, coating (Chemistry)
Classification: CPC C  H | IPC C  H

Claim 0:
1. A silicon single crystal wafer for a multilayer structure device, wherein
the silicon single crystal wafer is composed of an NV region,
has at least a DZ layer and a BMD layer which is positioned immediately below the DZ layer in order from a surface of the silicon single crystal wafer,
the DZ layer has a thickness of 5 to 12.5 μm and the BMD layer has a BMD density of 1×1011/cm3 or higher,
when a dent with a dent depth of Depth on the surface of the silicon single crystal wafer is formed so as to satisfy a relational equation

Depth=3×Fz0.6 

where Depth is a dent depth (unit: μm), Fz is a pushing pressure (unit: N), and Depth is 0.01 μm or more and less than 5.00 μm,

by applying the pushing pressure Fz, the silicon single crystal wafer has a stacked structure with at least 3 layers including a strained layer, a DZ layer, and a BMD layer in order from the surface, and
when the silicon single crystal wafer having the dent formed is subjected to a heat treatment at a temperature of 900° C. for 1 hour, a rosette length of a dislocation of the DZ layer after the heat treatment becomes shorter than a rosette length of a dislocation of the DZ layer before the heat treatment.