title: Development of Gated Pinned Avalanche Photodiode Pixels for High-Speed Low-Light Imaging.
abstract: This work explores the benefits of linear-mode avalanche photodiodes (APDs) in high-speed CMOS imaging as compared to different approaches present in literature. Analysis of APDs biased below their breakdown voltage employed in single-photon counting mode is also discussed, showing a potentially interesting alternative to existing Geiger-mode APDs. An overview of the recently presented gated pinned avalanche photodiode pixel concept is provided, as well as the first experimental results on a 8 × 16 pixel test array. Full feasibility of the proposed pixel concept is not demonstrated; however, informative data is obtained from the sensor operating under -32 V substrate bias and clearly exhibiting wavelength-dependent gain in frontside illumination. The readout of the chip designed in standard 130 nm CMOS technology shows no dependence on the high-voltage bias. Readout noise level of 15 e - rms, full well capacity of 8000 e - , and the conversion gain of 75 µV / e - are extracted from the photon-transfer measurements. The gain characteristics of the avalanche junction are characterized on separate test diodes showing a multiplication factor of 1.6 for red light in frontside illumination.
authors.affiliation: KU Leuven, ESAT, Kasteelpark Arenberg 10, B-3001 Leuven, Belgium. tomislav.resetar@imec.be.|Imec, Kapeldreef 75, B-3001 Leuven, Belgium. tomislav.resetar@imec.be.
authors.forename: Tomislav
authors.initials: T
authors.lastname: Resetar
authors.affiliation: Imec, Kapeldreef 75, B-3001 Leuven, Belgium. koen.demunck@imec.be.
authors.forename: Koen
authors.initials: K
authors.lastname: De Munck
authors.affiliation: Imec, Kapeldreef 75, B-3001 Leuven, Belgium. luc.haspeslagh@imec.be.
authors.forename: Luc
authors.initials: L
authors.lastname: Haspeslagh
authors.affiliation: Imec, Kapeldreef 75, B-3001 Leuven, Belgium. Maarten.Rosmeulen@imec.be.
authors.forename: Maarten
authors.initials: M
authors.lastname: Rosmeulen
authors.affiliation: Imec, Kapeldreef 75, B-3001 Leuven, Belgium. andreas.suess@imec.be.
authors.forename: Andreas
authors.initials: A
authors.lastname: Süss
authors.affiliation: KU Leuven, ESAT, Kasteelpark Arenberg 10, B-3001 Leuven, Belgium. puers@esat.kuleuven.be.|Imec, Kapeldreef 75, B-3001 Leuven, Belgium. puers@esat.kuleuven.be.
authors.forename: Robert
authors.initials: R
authors.lastname: Puers
authors.affiliation: KU Leuven, ESAT, Kasteelpark Arenberg 10, B-3001 Leuven, Belgium. chris.vanhoof@imec.be.|Imec, Kapeldreef 75, B-3001 Leuven, Belgium. chris.vanhoof@imec.be.
authors.forename: Chris
authors.initials: C
authors.lastname: Van Hoof
keywords: APD; CIS; CMOS; PAPD; avalanche photodiode; high-speed; image sensor; pinned; pixel