Photodiodes(Wavelength 180-200nm) | SIMTRUM Photonics Store

Our photodiodes (180–200 nm wavelength) are ideally suited for the following applications:

• DUV photolithography systems
• Excimer lasers
• DUV/VUV light sources
• VUV ultraviolet spectrometers
• Space astronomy observations
• VUV synchrotron radiation source monitoring

DUV/VUV photons carry energy far exceeding the bandgap of silicon carbide (SiC). As a result, incident photons can excite electrons from the valence band to the conduction band within an extremely shallow depth near the material surface, instantaneously generating electron-hole pairs. Simultaneously, a strong electric field region is formed within the depletion region—located at a depth of several nanometers to tens of nanometers in the outermost layer of the device. Under the influence of this strong electric field, photogenerated electrons and holes drift rapidly in opposite directions: electrons move toward the n-type region, while holes migrate to the p-type region. This directional carrier movement generates a photocurrent in the external circuit, whose intensity is proportional to the incident DUV/VUV light intensity, thereby enabling precise detection and measurement of DUV/VUV radiation.

Furthermore, owing to SiC’s inherent advantages—including high critical displacement energy, low intrinsic carrier concentration, and excellent high-temperature stability—the device achieves high quantum efficiency (QE), outstanding radiation resistance, and low dark current.

Q: How to choose between TO packaging and ceramic packaging?

A: Ceramic packaging uses hermetic sealing, while TO packaging is mostly non-hermetic or resin-filled sealed. Therefore, ceramic packaging is more recommended for harsh environments. Additionally, ceramic packaging has a higher thermal conductivity, which is more conducive to device stability, but it is also more expensive than TO packaging.