Photon-timing jitter dependence on the injection position in single-photon avalanche diodes

Abstract

In recent years a growing number of applications demands always better timing resolution for Single Photon Avalanche Diodes. The challenge is pursuing the improved timing resolution without impairing the other device characteristics such as quantum efficiency and dark counts. This task requires a clear understanding of the physical mechanisms necessary to drive the device engineering process. Past studies state that in Si-SPADs the avalanche injection position statistics is the main contribution to the photon-timing jitter. However, in recent re-engineered devices, this assumption is questioned. For the purpose of assessing for good this contribution we developed an experimental setup in order to characterize the photontiming jitter as a function of the injection position by means of TCSPC measurements with a laser focused on the device active area. Results confirmed not only that the injection position is not the main contribution to the photon-timing jitter but also evidenced a radial dependence never observed before. Furthermore we found a relation between the photon-timing jitter and the specific resistance of the devices. To characterize the resistances we studied the avalanche current density distribution in the device active area by imaging the photo-luminescence due to hot-carrier emission

Complete and Compact 32-Channel System for Time-Correlated Single-Photon Counting Measurements

“…As can be noticed, the time resolution increases with the SPAD excess bias voltage [27]. This behavior is due to the higher electric filed that makes the avalanche current grow faster; consequently, the statistic contributions to the avalanche current propagation have a reduced effect on the current time jitter [28]. Moreover, the time resolution is worsened when the conversion frequency increases.…”

Photon counting ladar work at FOI, Sweden

“…In this way the actual bandwidth or, in case of a SPAD, pulse length of the detector is not the limiting factor, but how accurately the rising flank of the pulse can be measured. For a SPAD the arrival time jitter is partly determined by the position on the detector where the photoelectron is generated, but also by other propagation statistics [23]. Another contribution to system timing uncertainty is the pulse length of the laser.…”

Engineering Breakdown Probability Profile for PDP and DCR Optimization in a SPAD Fabricated in a Standard 55 nm BCD Process

“…The physical construction of this buried layer has direct consequences for the timing response. Considering the light absorption length of the silicon, the thickness of the n-well region contributes to the diffusion tail while the overall resistivity of the path to the cathode contact and avalanche spreading dynamics determines the fullwidth at half-maximum (FWHM) of the timing jitter [19], [20]. Furthermore, the buried n-well, which can be designed with retrograde doping, aids in the design of the multiplication and space-charge regions which is key for low-noise operation [21].…”