Laser annealing heals radiation damage in avalanche photodiodes

EPJ Quantum Technology

Table 1 Summary of detector samples, applied radiation, previous thermal annealing, and measured results of laser annealing

Sample ID	106 MeV proton fluence ( \(\boldsymbol{\mathrm{cm}^{-2}}\) )	Equivalent time in 600 km polar orbit (months)	Thermal annealing procedure	Dark count rate at \(\boldsymbol{{-}80^{\circ}\mathrm{C}}\)				Annealing power (W)	\(\boldsymbol{V_{\text{excess}}}\) (V)
Sample ID		Equivalent time in 600 km polar orbit (months)	Thermal annealing procedure	Before (Hz)	Lowest after (Hz)	Highest reduction factor	Typical for pre-radiation (Hz)	Annealing power (W)	\(\boldsymbol{V_{\text{excess}}}\) (V)
C30902SH-1	10⁹	6	None	347	2.3	150	∼5	0.8	14
C30902SH-2	10⁹	6	None	363	2.64	137	∼5	1.5	14
SLiK-1	10⁸	0.6	\(2~\mathrm{h}~@~{+}100^{\circ}\mathrm{C}\)	6.71	0.16	41.7	<1	1.4	14
SLiK-2	10⁸	0.6	\(2~\mathrm{h}~@~{+}100^{\circ}\mathrm{C}\)	2.19	0.42	5.3		0.8	14
SLiK-3	4 × 10⁹	24	\(4~\mathrm{h}~@~{+}80^{\circ}\mathrm{C}\), \(2~\mathrm {h}~@~{+}100^{\circ}\mathrm{C}\)	43.1	2.09	21		1.4	14
SLiK-4	10⁹	6	None	192	8.3	23		1.0	20
SLiK-5	4 × 10⁹	24 (applied bias voltage)	\(3~\mathrm {h}~@~{+}80^{\circ}\mathrm{C}\), \(2~\mathrm{h}~@~{+}100^{\circ}\mathrm{C}\)	447	58	7.7		1.0	20
SAP500S2-1	4 × 10⁹	24	\(4~\mathrm{h}~@~{+}80^{\circ}\mathrm{C}\), \(2~\mathrm{h}~@~{+}100^{\circ}\mathrm{C}\)	1,579	2.08	758	∼2	1.4	20
SAP500S2-2	10⁸	0.6	\(2~\mathrm{h}~@~{+}100^{\circ}\mathrm{C}\)	213	1.66	128	∼2	1.6	20

The detectors are referred to by the given sample IDs throughout the paper. The highest reduction factor is the ratio between the reference dark count rate before any laser annealing and the lowest dark count rate after laser annealing - the corresponding laser power for this is also given. We include typical pre-radiation dark count rates of each model under the same bias and temperature conditions [35, 37].