Red-Enhanced Photon Detection Module Featuring a $32 \times 1$ Single-Photon Avalanche Diode Array

In this letter, the development and the experimental characterization of a new photon detection module, based on a 32 × 1 red-enhanced single-photon avalanche diode (RE-SPAD) array, are presented. A custom-developed technology has been exploited to design a detector having large-area pixels (50-μm diameter) with optimized performance. With an excess bias voltage V
_ov
= 15 V, a photon detection efficiency as high as 57% at 600 nm (33% at 800 nm) is achieved, along with a dark count rate in the kHz range and optical crosstalk probability as low as 0.29%. The remarkable detection efficiency of the RE-SPAD array makes the module particularly suitable for all applications where high-detection efficiency in the red/near-infrared range is mandatory. As an example, the performance of the array module is demonstrated to match the demanding requirements of multispot single-molecule fluorescence spectroscopy.