Method for producing bonded wafer
First Claim
1. A method for producing a bonded wafer, comprising a step of implanting oxygen ions from a surface of a wafer for active layer to form an oxygen ion implanted layer at a given position inside the wafer for active layer;
- a step of bonding the wafer of active layer to a wafer for support substrate directly or through an insulating film so as to form a bonded wasfer;
a step of subjecting the resulting bonded wafer to a heat treatment for increasing a bonding strength;
a step of removing a portion of the wafer for active layer in the bonded wafer to a given position not exposing the oxygen ion implanted layer by a given method;
a step of exposing the entire surface of the oxygen ion implanted layer; and
a step of removing the exposed oxygen ion implanted layer to obtain an active layer of a given thickness, wherein the step of exposing the entire surface of the oxygen ion implanted layer is carried out by a dry etching under given conditionswherein the oxygen ion implanted layer has an oxygen concentration peak of not less than 1×
1022 atoms/cm3 and satisfies a relationship of Re>
2×
{(ts)/(to)}×
{(De+Dt)/(100−
De)} when a thickness and a variation in an in-plane thickness of a silicon layer in the wafer for active layer on the oxygen ion implanted layer before the dry etching are ts and ±
Dt %, respectively, and a thickness of the oxygen ion implanted layer is to and an etching rate ratio of Si to silicon oxide film (Si/SiOx) is Re and a variation in an in-plane etching is ±
De %.
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Accused Products
Abstract
A bonded wafer is produced by comprising a step of implanting oxygen ions from a surface of a wafer for active layer to form an oxygen ion implanted layer at a given position inside the wafer for active layer; a step of bonding the wafer of active layer to a wafer for support substrate directly or through an insulating film; a step of subjecting the resulting bonded wafer to a heat treatment for increasing a bonding strength; a step of removing a portion of the wafer for active layer in the bonded wafer to a given position not exposing the oxygen ion implanted layer by a given method; a step of exposing the entire surface of the oxygen ion implanted layer; and a step of removing the exposed oxygen ion implanted layer to obtain an active layer of a given thickness, wherein the step of exposing the entire surface of the oxygen ion implanted layer is carried out by a dry etching under given conditions.
31 Citations
3 Claims
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1. A method for producing a bonded wafer, comprising a step of implanting oxygen ions from a surface of a wafer for active layer to form an oxygen ion implanted layer at a given position inside the wafer for active layer;
- a step of bonding the wafer of active layer to a wafer for support substrate directly or through an insulating film so as to form a bonded wasfer;
a step of subjecting the resulting bonded wafer to a heat treatment for increasing a bonding strength;
a step of removing a portion of the wafer for active layer in the bonded wafer to a given position not exposing the oxygen ion implanted layer by a given method;
a step of exposing the entire surface of the oxygen ion implanted layer; and
a step of removing the exposed oxygen ion implanted layer to obtain an active layer of a given thickness, wherein the step of exposing the entire surface of the oxygen ion implanted layer is carried out by a dry etching under given conditionswherein the oxygen ion implanted layer has an oxygen concentration peak of not less than 1×
1022 atoms/cm3 and satisfies a relationship of Re>
2×
{(ts)/(to)}×
{(De+Dt)/(100−
De)} when a thickness and a variation in an in-plane thickness of a silicon layer in the wafer for active layer on the oxygen ion implanted layer before the dry etching are ts and ±
Dt %, respectively, and a thickness of the oxygen ion implanted layer is to and an etching rate ratio of Si to silicon oxide film (Si/SiOx) is Re and a variation in an in-plane etching is ±
De %. - View Dependent Claims (2, 3)
- a step of bonding the wafer of active layer to a wafer for support substrate directly or through an insulating film so as to form a bonded wasfer;
Specification