GaNo Opto releases the world first commercial SiC UV APD

Author:GaNo Optoelectronics    Posted:2016-01-12

    GaNo Optoelecteronics Inc of Jiangsu, China ( has released the world first commercial UV avalanche photodiodes (APDs) based on SiC. The intrinsically visible-blind APD can work in either linear or Geiger mode with UV photon counting capability. GaNo Opto is a leading company for UV light sensing solution, which offers UV sensors and modules based on wide-bandgap semiconductors including GaN and SiC.


Fig. 1  Room temperature photo and dark current characteristics of the SiC APD.

    SiC UV APDs have attracted much attention from both academics and industry because of their potential applications in corona discharge and flame detection, UV fluorescence, UV astronomy, UV ladar and communication, as well as detection of jet engines and missile plumes. Traditionally, bulky photomultiplier tubes (PMTs) have to be used in these applications, where the UV signals to be detected could be very weak. SiC APDs are a promising alternative to replace PMTs, when ruggedness, compactness, low cost, long lifetime, and low voltage operation are needed. However, implementation of SiC UV APDs is very challenging due to substrate or epi-related material defects, relatively not-well modeled device operation, and immature device processing technology. Most recently, GaNo Opto has started volume production of high performance SiC APDs with what is said to be high gain up to 106 and capable of single photon counting combined with low dark count rate of ~1 Hz/m2 at room temperature. Under special conditions, the device could even conduct single UV photon counting at high temperatures up to 150 oC, it is reckoned.    

 Fig. 2  Real-time photon counting spectrum of the SiC APD.

    “It has been well accepted that wide bandgap semiconductor is the most suitable material for making UV photodetectors. Although commercially available Si APDs demonstrate moderate quantum efficiency in the UV wavelength range, they require highly expensive optical filters to achieve a high UV/visible rejection ratio as their peak response stays within the visible wavelength range. In addition, Si APDs with very low dark counts were only demonstrated when they were cooled to liquid nitrogen temperatures.” says GaNo Opto’s CTO Dr. Hai Lu, who is also the distinguished professor of Nanjing University, China. “Our process shows that appropriate termination and surface passivation techniques are critical for realizing SiC APDs with low leakage current and resulting high avalanche gain, both of which are necessary for the device to operate in single photon counting mode. Leakage current as low as in sub-pA level is achieved at 98% breakdown voltage. ” he adds. “Our next step is to develop UV imaging arrays based on SiC APDs. In this case, uniformity among each APD pixels and scalability would be the main technological barriers. New implantation and dopant activation sequences, and backend processing techniques are being developed to achieve this goal.” Hai reckons. 

    About GaNo Opto

    GaNo Opto is the total solution specialist in UV detection technology. GaNo Opto’s products are based on wide bandgap semiconductors like Gallium Nitride (GaN) and Silicon Carbide (SiC). They used this technology to supply high performance UV sensors for a wide range of applications including UV curing, UV index monitoring, UV water/air sterilization, corona discharge and flame detection, and etc. 

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