Photo-sensitive silicon package embedding self-powered electronic system

摘要

A self-powered electronic system comprises a first chip (401) of single-crystalline semiconductor embedded in a second chip (302) of single-crystalline semiconductor shaped as a container bordered by ridges. The assembled chips are nested and form an electronic device assembled, in turn, in a slab of weakly p-doped low-grade silicon shaped as a container (330) bordered by ridges (331). The flat side (335) of the slab includes a heavily n-doped region (314) forming a pn-junction (315) with the p-type bulk. A metal-filled deep silicon via (350) through the p-type ridge (331) connects the n-region with the terminal (322) on the ridge surface as cathode of the photovoltaic cell with the p-region as anode. The voltage across the pn-junction serves as power source of the device.

主权项

1. A semiconductor device comprising:
an integrated circuit (IC) chip having a first side with terminals of the IC, an opposite second side, and a thickness; a slab of low-grade silicon (l-g-Si) having a first side lightly p-doped, covered by an insulating layer and configured as a ridge framing a depression including a recessed central area suitable to accommodate the chip, and the opposite second side heavily n-doped to form the pn-junction of a photovoltaic cell; the ridge having a first surface in a first plane, and the recessed central area having a second surface in a second plane spaced from the first plane by a depth at least equal to the chip thickness; the ridge covered by a metal layer configured as device terminals, and the central area covered by a metal layer configured as attachment pads for the IC terminals with one pad connected to a metal-filled deep-silicon via extending from the central area to the pn-junction; and the terminals of the chip attached to the pads of the central slab area so that the second chip side is co-planar with the device terminals on the slab ridge, whereby the slab serves as the package of the IC chip and the photovoltaic cell powers the IC.