SOI wafer and method for producing it

• Main Authors: ZEMKE DIRK, BLIETZ MARKUS, MILLER ALFRED, WAHLICH REINHOLD, GRAEF DIETER
• Format: Patent
• Language: English
• Published: 01.07.2008
• Subjects: AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUSPOLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR; BASIC ELECTRIC ELEMENTS; CHEMISTRY; CRYSTAL GROWTH; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; METALLURGY; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; REFINING BY ZONE-MELTING OF MATERIAL; SEMICONDUCTOR DEVICES; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; SINGLE-CRYSTAL-GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL ORUNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL

An SOI wafer is constructed from a carrier wafer and a monocrystalline silicon layer having a thickness of less than 500 nm, an excess of interstitial silicon atoms prevailing in the entire volume of the silicon layer. The SOI wafers may be prepared by Czochralski silicon single crystal growth, the condition v/G<(V/G)crit=1.3x10-3 cm2/(K.min) being fulfilled at the crystallization front over the entire crystal cross section, with the result that an excess of interstitial silicon atoms prevails in the silicon single crystal produced; separation of at least one donor wafer from this silicon single crystal, bonding of the donor wafer to a carrier wafer, and reduction of the thickness of the donor wafer, with the result that a silicon layer having a thickness of less than 500 nm bonded to the carrier wafer remains.