Research

Infrared detectors can see spectral wavelengths that silicon CSI cameras can't detect. Therefore, important information can be obtained by using SWIR (1-2.4 micron), MWIR (3-5 micron), and LWIR (8-12 micron) detectors. SWIR detectors are useful to observe scenes farther than Si CSI cameras because of much reduced dust scattering. MWIR detectors track hot objects such as missiles since those at 700K-1000K have peak emission in the MWIR region. LWIR detectors including high speed photon detectors (MgCdTe, T2SL, GaAs-based QWIP) and microbolometer (VOx, a-Si, TiO2) are the choice to detect objects at room-temperature (~300 K). 

Our group investigates next-generation infrared detectors using III-V materials. Multi-color detectors are demonstrated by epitaxially integrating SWIR (InGaAs) and MWIR (InAs) bands in a back-to-back pnp diode, two-terminal configuration structure. Flexible infrared InAs arrays are also studied via hetero-epitaxial lift-off (hetero ELO) process. Metamorphic InAsSb for 0.1 eV (12 micron) bulk detectors are also interesting since it is the suitable III-V material for LWIR detection.