Importance

Loading Importance Indicators...

Abstract

A method for making a semiconductor device from a plurality of semiconductor substrates includes the steps of: processing at least one surface of at least one of the substrates; thinning at least one of the substrates; bonding the processed and thinned substrates together so that the at least one processed surface defines an outer surface of the semiconductor device; and annealing the bonded together substrates at a relatively low anneal temperature so as to not adversely effect the at least one processed surface. The step of thinning preferably comprises removing a surface portion of the least one substrate opposite the processed surface, to a thickness of less than about 200 .mu.m. A gettering layer may be formed for the at least one substrate prior to thinning. Accordingly, the step of thinning removes the gettering layer. An implanted region may be formed at a surface of the at least one substrate opposite the processed surface prior to bonding. The implanting may comprise implanting with a lifetime killing implant or a dopant. An epitaxial layer may be formed on the backside of a substrate. The step of processing may include forming a metal layer. Thus, the anneal temperature is preferably less than a temperature related to a characteristic of the metal layer. For an aluminum layer, the anneal temperature is preferably less than about 450.degree. C. If a barrier metal is used between the aluminum and substrate, the anneal temperature may be in a range of about 450 to 550.degree. C.

Loading the Abstract Image...

First Claim