UV Optimised APDs for Extremely Sensitive Light Detection

Laser Components designs a wide range of avalanche photodiodes (APDs) with market leading performance, optimised for different application requirements. These extremely sensitive detectors are capable of detecting light levels down to single photons. Recent developments include a reach-through epitaxial structure with input surface optimised for UV sensitivity. Ultraviolet photons have high energy, which means their absorption depth in silicon is extremely shallow. In conventional photodiodes and APDs, most UV light signal is lost to either reflection, absorption or recombination in the input surface structure leading to very low sensitivity. Laser Components have developed an extremely thin P+ deposition layer, which minimises recombination and enables extremely high sensitivity to short wavelength light to be achieved. An anti-reflection coating can also be applied with thickness tuned for minimum reflection of specific wavelengths. 

APDs in the range include: SAE series - silicon epitaxial structure enables fast response time and low noise; SAR series - silicon reach-through structure with deep absorption region and very low noise; SUR series - silicon epitaxial structure with surface optimised for UV short wavelengths; SAP series - optimised for single photon counting in Geiger mode; SAHA series - silicon, mass production, low cost, low operating voltage; IAG series - InGaAs APD designed for NIR 1000nm-1630nm wavelengths. High gain (M>30), low noise.  

Laser Components can also offer APD arrays as well as APD drive electronics and modules for both linear and Geiger mode operation, which provide a simple way to evaluate APD capability.  Requests for custom variants are also welcomed.