Biosensor system package and method for fabricating the same

A biosensor system package includes: a transistor structure in a semiconductor layer having a front side and a back side, the transistor structure comprising a channel region; a multi-layer interconnect (MLI) structure on the front side of the semiconductor layer, the transistor structure being electrically connected to the MLI structure; a carrier substrate on the MLI structure; a first through substrate via (TSV) structure extending though the carrier substrate and configured to provide an electrical connection between the MLI structure and a separate die; a buried oxide (BOX) layer on the back side of the semiconductor layer, wherein the buried oxide layer has an opening on the back side of the channel region, and an interface layer covers the back side over the channel region; and a microfluidic channel cap structure attached to the buried oxide layer.