Single Photon Counting UV Solar-Blind Detectors Using Silicon and III-Nitride Materials

Area of Science:

• Astronomy
• Cosmology
• Planetary Science
• Biological Applications
• Medical Applications

Background:

• Ultraviolet (UV) research necessitates precise detection of faint objects, often requiring photon-counting capabilities.
• Existing technologies face challenges in achieving high quantum efficiency (QE) and solar blindness in the UV spectrum.

Purpose of the Study:

• To present and evaluate two distinct approaches for achieving photon-counting detection in the UV range.
• To detail methods for enhancing UV quantum efficiency and enabling solar-blind detection.

Main Methods:

• UV enhancement of silicon-based photon-counting detectors (electron multiplying charge-coupled devices, avalanche photodiodes) using molecular beam epitaxy for delta doping and superlattice doping.
• Application of atomic layer deposition for antireflection (AR) and solar-blind UV bandpass coatings.
• Development of III-nitride material-based avalanche photodiodes for UV detection.

Main Results:

• Silicon detectors achieved >50% QE in the 100-300 nm range with simple AR coatings.
• Complex AR coatings resulted in approximately 80% QE at ~206 nm for silicon detectors.
• III-nitride avalanche photodiodes demonstrated high QE and intrinsic solar blindness.

Conclusions:

• Both silicon detector enhancement and III-nitride avalanche photodiodes offer viable solutions for UV photon-counting applications.
• Advanced doping and coating techniques significantly improve UV detector performance.
• The developed methods cater to demanding UV detection requirements across various scientific fields.