Patent ID: 8242013

Claim:
A method of making a thin-substrate composite power semiconductor device (TSCPSD) comprising a power semiconductor device (PSD) made out of a semiconductor device material, a front-face device carrier (FDC) made out of a carrier material, and an intervening bonding layer (IBL) wherein the PSD has a back substrate portion and a front semiconductor device portion with patterned front-face device metallization pads and wherein the PSD additionally has a diminishing thickness TPSD in that it is comparable to the thickness of the front semiconductor device portion, the method comprises: fabricating the PSD with a semiconductor wafer process on an interim back substrate of thickness TIBS, where TIBS is greater than TPSD and where TIBS being large enough for compatibility with the semiconductor wafer process; providing the FDC with a thickness TFDC large enough to provide sufficient structural rigidity to the TSCPSD; providing the IBL and bonding the separately provided FDC of thickness TFDC to the separately fabricated PSD of thickness TIBS with the IBL thus forming a sandwiched FDC, IBL and PSD; on the FDC, fabricating a plurality of front-face carrier metallization pads and a plurality of through-carrier conductive vias respectively connecting the front-face carrier metallization pads to the front-face device metallization pads; and thinning the interim back substrate from the thickness TIBS until the corresponding PSD thickness is reduced to TPSD then forming back metallization thereon.