Innovative SPAD-Based Quantum Random Number Generator Unveiled at International Workshop

We are proud to contribute to the International #SPAD #Sensor Workshop at Yonsei University, Seoul. Benjamin Saft, Alexander Zimmer, Jakob Hampel, Daniel Gäbler, Maximilian Wiener, and Eric Schäfer from IMMS and X-FAB worked on a fully electrical SPAD-based #quantum random number generator (QRNG) using an on-chip trigger diode as fully #CMOS integrated approach.

So far – in conventional SPAD-based QRNG concepts:
➡ Entropy is typically derived from spontaneous photon emission of a weak LED.
➡ Photon arrival statistics are converted into bit streams.
➡ The need for an external optical source is limiting a full monolithic integration.

New solution:
➡ The trigger diode is used to initiate SPAD events while enabling electrical tuning of the event rate.
➡ A Test chip was implemented in X-FAB XH018 technology.
➡ Experimental results show suitability as QRNG entropy source under special operating conditions.
➡ No dependence on external optical illumination in SPAD-based QRNGs
➡ Enables compact, scalable, fully integrated quantum entropy sources
➡ Relevant for secure hardware, embedded cryptography, and on-chip security systems

For more detail on the IMMS part of this development, you are welcome to contact Benjamin Saft or Eric Schäfer directly. General information on our research on integrated sensor systems can be found under www.imms.de/sensor-ics.

Funding:

This work in the projects FluoResYst, ScoreChip and PANDIA has been funded by the Federal Ministry of Research, Technology and Space (BMFTR) under the reference 13N15807 and by the German Land of Thüringen and the European Union under the references 1001607/2024 VFE 0059 and 1004537/2025 VFE 0027.