Thick position-sensitive silicon detectors using a wafer bonding technique

We have shown that a wafer-bonded silicon power transistor, consisting of two thin device wafers bonded onto either side of a 2 mm-thick high-resistivity silicon wafer, functions as an X-ray detector. The hydrophobic bonding process was performed at 400°C. This low temperature wafer bonding technique should enable the development of large-area, position-sensitive detectors, using thick, high-resistivity intrinsic silicon bonded to thin readout wafers fabricated using conventional CMOS technology. These devices should enable fabrication of thicker intrinsic silicon detectors than currently available. Thick, position-sensitive detectors based on double-sided strip detectors and pixellated detectors will be possible. Applications for such detectors include X-ray and gamma-ray astrophysics, nuclear medicine, nuclear physics, and homeland defense. We present initial results obtained with devices made using this wafer bonding process.