High temperature AlInP X-ray spectrometers

Abstract

Two custom-made Al 0.52 In 0.48 P p + -i-n + mesa photodiodes with different diameters (217 µm ± 15 µm and 409 µm ± 28 µm) and i layer thicknesses of 6 µm have been electrically characterised over the temperature range 0 °C to 100 °C. Each photodiode was then investigated as a high-temperature-tolerant photon counting X-ray detector by connecting it to a custom-made low-noise charge-sensitive preamplifier and illuminating it with an 55 Fe radioisotope X-ray source (Mn Kα = 5.9 keV; Mn Kβ = 6.49 keV). At 100 °C, the best energy resolutions ( full width at half maximum at 5.9 keV) achieved using the 217 µm ± 15 µm diameter photodiode and the 409 µm ± 28 µm diameter photodiode were 1.31 keV ± 0.04 keV and 1.64 keV ± 0.08 keV, respectively. Noise analysis of the system is presented. The dielectric dissipation factor of Al 0.52 In 0.48 P was estimated as a function of temperature, up to 100 °C. The results show the performance of the thickest Al 0.52 In 0.48 P X-ray detectors so far reported at high temperature. The work has relevance for the development of novel space science instrumentation for use in hot space environments and extreme terrestrial applications.

Nanoparticles in analytical laser and plasma spectroscopy – a review of recent developments in methodology and applications

“…Compared to standard LIBS, NELIBS gave two orders of magnitude lower detection limit for these contaminants and allowed to perform mapping measurements on vegetable leaves. 556 Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICPMS) is another highly sensitive and fast analytical technique, allowing to perform elemental analysis on solid samples by ablating their surface and determining the composition of the formed particulate material via mass spectrometry. 562 It requires little or no sample preparation, the analysis can be performed on conducting, non-conducting, opaque and transparent materials; and allows to perform bulk analysis, depth proling or elemental/isotope mapping.…”

Wide bandgap semiconductor conversion devices for radioisotope microbatteries

“…The intended diameter of the devices was 400 μm. Previous measurements of the diameter of a 6 μm thick i layer AlInP device fabricated using an identical fabrication process as for the 6 μm thick i layer AlInP device reported here, were performed using an optical microscope to investigate the potential effect of the fabrication process to its diameter [21]; the measurement suggested a diameter of 409 µm ± 28 µm, and it was thus inconclusive as to whether the modified etching recipe used for the 6 μm thick i layer AlInP device affected its diameter. As such, all five devices were considered to have an area of 0.126 mm 2 .…”

Impact Ionization Coefficients in (Al x Ga1-x )0.52In0.48P and Al x Ga1-x As Lattice-Matched to GaAs

“…AlGaInP APDs exhibit negligible dark currents even at fields close to breakdown [4], and the excess noise factor in thin AlInP devices has been shown to be similar to that in silicon [5]. The wide bandgap of AlGaInP also results in minimal variation in breakdown voltage and dark currents with temperature [6], [7] and AlInP X-ray detectors with good high-temperature performance have been reported [8]. The dark currents and temperature dependence characteristics of AlInP and GaInP devices [6] compare favorably with recently reported GaN APDs grown on GaN substrates [9], but with the advantage of the low cost and mature technology associated with GaAs substrates.…”