POSTGROWTH TUNING OF QUANTUM-WELL INFRARED DETECTORS BY RAPID THERMAL ANNEALING

The peak detection wavelength of an operational quantum-well infrared photodetector structure has been red shifted using rapid thermal annealing to partially intermix the well and barrier layers. Successive anneals at 850-degrees-C were used to tune an 8.13 muM detector continuously out to 9.13 muM. All of the fabricated detectors were operational in spite of very long annealing times of up to 300 s. The peak spectral responsivity at a device current of 10 muA dropped from 0.62 to 0. 12 A/W after the longest anneal time, but the broadband responsivity only dropped by a factor of 3 due to a simultaneous increase in the detection spectral bandwidth.