Wafer-Bonded Silicon Gamma-Ray Detectors

Direct hydrophobic wafer bonding was used to create a 1 mm thick gamma-ray detector from two 0.5 mm thick wafers. Full depletion and efficient charge transport across the wafer bond is demonstrated. The energy resolution of the detector is 8.9 keV FWHM for 60 keV gamma rays at room temperature with a leakage of 3.5 muA while operating at 700 V. Improvements in the technique should allow for thicker detectors with better energy resolution.