Shallow-trench-isolation bounded single-photon avalanche diodes in commercial deep submicron CMOS technologies
This dissertation describes the first single-photon detection device to be manufactured in a commercial deep-submicron CMOS technology. It also describes novel self-timed peripheral circuits which optimize the performance of the new device. An extension of the new device for dual-color single-photon detection is investigated. Finally, an area- and power-efficient method for single-photon frequency upconversion is presented, analyzed, and experimentally examined.
Single-photon avalanche diodes have been used in diverse applications, including three-dimensional laser radar, three-dimensional facial mapping, fluorescence-correlation techniques and time-domain tomography. Due to the high electric fields which these devices must sustain, they have traditionally been manufactured in custom processes, severely limiting their speed and the ability to integrate them in high-resolution imagers. By utilizing a process module originally designed to enhance the performance of CMOS transistors, we achieve highly planar junctions in an area-efficient manner. This results in SPADs exhibiting high fill factors, small pitch and ultrafast operation. Device miniaturization is accompanied by excessive noise, which was shown to emanate from trapped avalanche charges. Due to the fast recharging of the device, these charges are released in a subsequent charged phase of the device, causing correlated after-pulses. We present electrostatic and electrical simulation results, as well as a comprehensive characterization of the new device. We also show for the first time that by utilizing the two junctions included in the device, we can selectively detect photons of different wavelengths in the same pixel, as is desirable in cross-correlation experiments.
This dissertation also describes an efficient new method for single-photon frequency upconversion. This is desirable for applications including quantum-key distribution and high-resolution near-infrared imaging. The new technique is based on electroluminescence in or near the multiplication region of the device, resulting from hot-carrier recombination. We model a proposed hybrid device and deduce the critical parameters for efficient upconversion. Lastly, we experimentally demonstrate that the electroluminescence yield from an InGaAs/InAlAs avalanche diode is sufficient for highly-efficient upconversion.