We discuss the benefits of using microoptics concentration arrays in connection with image (or pixellated) photodetectors, in terms of: 1) recovery of area fill-factor; 2) reduction of equivalent dark-current; 3) mitigate dead-time issues; and 4) improved dynamic range. As an example of application, we describe the fill-factor recovery in connection to an array of 32x32 6-micron diameter, 50-micron pitch, single photon avalanche detector (SPAD). We use a 32x32 array of microlenses, fabricated by polymer casting in a photoresist replica mold.We demonstrate, for the first time to the best of our knowledge, an increase by a factor x25 of the effective spectral sensitivity of the final device. The lens array itself allows a recovery, and projected improvements in excess of appear feasible.
Improving Photodetector Performance by Means of Microoptics Concentrators
DONATI, SILVANO;MARTINI, GIUSEPPE;RANDONE, ENRICO MARIA
2011-01-01
Abstract
We discuss the benefits of using microoptics concentration arrays in connection with image (or pixellated) photodetectors, in terms of: 1) recovery of area fill-factor; 2) reduction of equivalent dark-current; 3) mitigate dead-time issues; and 4) improved dynamic range. As an example of application, we describe the fill-factor recovery in connection to an array of 32x32 6-micron diameter, 50-micron pitch, single photon avalanche detector (SPAD). We use a 32x32 array of microlenses, fabricated by polymer casting in a photoresist replica mold.We demonstrate, for the first time to the best of our knowledge, an increase by a factor x25 of the effective spectral sensitivity of the final device. The lens array itself allows a recovery, and projected improvements in excess of appear feasible.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
