High-Performance Long-Wavelength Infrared HgCdTe Focal Plane Arrays Fabricated on CdSeTe Compliant Si Substrates

• Published in: IEEE transactions on electron devices Vol. 57; no. 4; pp. 782 - 787
• Main Authors: Wijewarnasuriya, P.S., Yuanping Chen, Brill, G., Zandi, B., Dhar, N.K.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.04.2010; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Arrays; Bolometer; infrared, submillimeter wave, microwave and radiowave receivers and detectors; Cadmium compounds; Cadmium selenides; CdSeTe; CdTe; compliant Si substrates; Current measurement; Detectors; Devices; Electronics; Exact sciences and technology; Focal plane; focal plane arrays (FPAs); HgCdTe; Imaging devices; infrared (IR) detectors; Infrared, submillimeter wave, microwave and radiowave instruments, equipment and techniques; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Intermetallics; long-wavelength IR; Mercury cadmium telluride; Mercury compounds; Microelectronic fabrication (materials and surfaces technology); Molecular beam epitaxy; molecular beam epitaxy (MBE); Optoelectronic devices; Photonics; Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Semiconductors; Silicon; Silicon substrates; Substrates; Tellurides; Tunneling; Performance evaluation; molecular beam epitaxy (MBE); High performance; Focal plane arrays; infrared (IR) detectors; Infrared detector; focal plane arrays (FPAs); Quantum yield; Photodetector; CdTe; longwavelength IR; Photovoltaic cell; compliant Si substrates; Military application; Far infrared radiation; Microelectronic fabrication; Optoelectronic device; Dark current; Molecular beam epitaxy; Current distribution; CdSeTe; HgCdTe; Thermal imaging
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2010.2041511

At the U.S. Army Research Laboratory, a new ternary semiconductor system CdSe x Te 1-x ,/Si(211) is being investigated as an alternative substrate to bulk-grown CdZnTe substrates for HgCdTe growth by molecular beam epitaxy. Long-wavelength (LW) photovoltaic devices fabricated on this compliant substrate material show diffusion limited performance at 78 K, indicating a high-quality material. The measured R 0 A at 78 K on ¿ co = 10 ¿m material is on the order of 340 ¿ · cm 2 . In addition to single devices, we have fabricated 256 × 256 2-D arrays with a 40-¿m pixel pitch on LW-HgCdTe grown on CdSe x Te 1-x /Si(211) compliant substrates. The data show an excellent quantum efficiency operability of 99% at 78 K under a tactical background flux of 6.7 × 10 15 ph/cm 2 s. The most probable dark current at peak distribution is 5.5 × 10 9 e-/s and is very consistent with the measured R 0 A values from single devices. This work demonstrates that CdSe x Te 1-x /Si(211) substrates provide a potential roadmap for more affordable robust third-generation focal plane arrays.