US 7,320,929 B2 | ||
Method of fabricating SOI wafer | ||
Hiroji Aga, Annaka (Japan); and Kiyoshi Mitani, Annaka (Japan) | ||
Assigned to Shin-Etsu Handotai Co., Ltd., Tokyo (Japan) | ||
Appl. No. 10/522,413 PCT Filed Jul. 16, 2003, PCT No. PCT/JP03/09007 § 371(c)(1), (2), (4) Date Jan. 26, 2005, PCT Pub. No. WO2004/012268, PCT Pub. Date Feb. 05, 2004. |
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Claims priority of application No. 2002-219308 (JP), filed on Jul. 29, 2002. | ||
Prior Publication US 2006/0040469 A1, Feb. 23, 2006 | ||
Int. Cl. H01L 21/30 (2006.01); H01L 21/46 (2006.01) |
U.S. Cl. 438—458 [438/459; 438/514; 438/526; 438/530; 257/E21.568; 257/E21.57] | 11 Claims |
1. A method of fabricating an SOI wafer comprising:
an insulating film formation step of forming an insulating film on a first main surface of at least one of a first substrate,
and a second substrate composed of silicon single crystal;
a separatory ion implanted layer formation step of forming a separatory ion implanted layer by implanting ions from an ion
implantation surface on the first main surface side of the second substrate;
a bonding step of bonding the second substrate having the separatory ion implanted layer formed therein and the first substrate
while opposing the first main surfaces with each other, and placing the insulating film in between;
a separation step of separating a bonded silicon single crystal film, later becoming an SOI layer, from the second substrate
at a position of the separatory ion implanted layer, the separation step forming a separation surface of the bonded silicon
single crystal film with a roughness (Rms) of 4.5 nm or less; and
a planarization step of planarizing having the separation surface side of the bonded silicon single crystal film so as to
produce the SOI layer,
wherein the separatory ion implanted layer formation step further includes, based on a desired thickness of the SOI layer,
adjusting a depth of formation of the separatory ion implanted layer measured from the ion implantation surface through control
of a magnitude of an ion implantation energy, and
wherein a dose of the ion implantation is lowered as the depth of formation of the separatory ion implanted layer measured
from the ion implantation surface becomes less, the dose of the ion implantation being such that the separation surface of
the bonded silicon single crystal film formed in the separation step has the roughness (Rms) of 4.5 nm or less.
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