Custom single-photon avalanche diode with integrated front-end for parallel photon timing applications.

Area of Science:

• Photonics and Optoelectronics
• Solid-State Devices
• Integrated Circuits

Background:

• Single-photon avalanche diodes (SPADs) are solid-state alternatives to photomultiplier tubes (PMTs) for single-photon timing.
• Custom SPADs offer excellent performance: low dark count rate (DCR), high photon detection efficiency (PDE), and precise temporal resolution (30 ps FWHM).
• Increasing demand for parallel measurement systems necessitates monolithic SPAD arrays, posing electrical challenges like crosstalk and timing resolution.

Purpose of the Study:

• To develop a pixel architecture for custom SPAD arrays that preserves individual channel performance.
• To address the electrical challenges of high parallel temporal resolution and minimized crosstalk in SPAD arrays.
• To enable the fabrication of high-performance SPAD arrays using custom technologies.

Main Methods:

• Proposed a novel pixel architecture integrating the timing signal pick-up circuit directly next to the photodiode.
• Modified the fabrication process flow for custom SPADs to integrate front-end electronics.
• Utilized an external standard CMOS active quenching circuit for stable performance at high count rates.

Main Results:

• Achieved a pixel architecture where each SPAD channel retains the performance of a single detector.
• Successfully minimized electrical crosstalk between channels in the array.
• Demonstrated stable timing performance at count rates exceeding 1 MHz.

Conclusions:

• The proposed pixel architecture enables the development of high-performance custom SPAD arrays.
• This approach overcomes limitations of standard CMOS technologies for SPAD array integration.
• The solution facilitates advanced parallel single-photon timing applications.