Characterization and analysis of InGaAsSb detectors

Abstract

Profiling of atmospheric CO 2 at 2 µm wavelength using the LIDAR technique, has recently gained interest. Although several detectors might be suitable for this application, an ideal device would have high gain, low noise and narrow spectral response peaking around the wavelength of interest. This increases the detector signal-to-noise ratio and minimizes the background signal, thereby increasing the device sensitivity and dynamic range. Detectors meeting the above idealized criteria are commercially unavailable for this particular wavelength. In this paper, the characterization and analysis of Sb-based detectors for 2 µm lidar applications are presented. The detectors were manufactured by AstroPower, Inc., with an InGaAsSb absorbing layer and AlGaAsSb passivating layer.The characterization experiments included spectral response, current versus voltage and noise measurements. The effect of the detectors bias voltage and temperature on its performance, have been investigated as well. The detectors peak responsivity is located at the 2 µm wavelength. Comparing three detector samples, an optimization of the spectral response around the 2 µm wavelength, through a narrower spectral period was observed. Increasing the detector bias voltage enhances the device gain at the narrow spectral range, while cooling the device reduces the cut-off wavelength and lowers its noise. Noise-equivalent-power analysis results in a value as low as 4x10 -12 W/Hz 1/2 corresponding to D* of 1x10 10 cmHz 1/2 /W, at -1 V and 20 o C. Discussions also include device operational physics and optimization guidelines, taking into account peculiarity of the Type II heterointerface and transport mechanisms under these conditions.

RECENT DEVELOPMENT OF SB-BASED PHOTOTRANSISTORS IN THE 0.9- TO 2.2-μM WAVELENGTH RANGE FOR APPLICATIONS TO LASER REMOTE SENSING

“…No antireflection coatings were applied. Figure 2 shows characterization setup 31 to obtain the detector characteristics in order to compare its performance with the requirement of the specific-application. The characterization experiments included spectral response, dark current and noise measurements, and its variation with bias voltage and temperature.…”

“…Several types of detectors might be suitable in the spectral range from visible-to 1.8-µm. However, detectors based on InGaAsSb and InGaAs materials were evaluated to obtain lower gain as compared to Si APD; and InGaAsSb detector has higher noise as compared to InGaAs detector and results were reported 31,[33][34] . On the other hand, the band gap of the active layers in AlGaAsSb/InGaAsSb phototransistors may be tuned in a way to provide maximum detectivity at a certain wavelength in a wide range of wavelengths between 0.6-to 2.4-micron.. We have identified a high performance phototransistor with the optimum spectral response for the DIAL application.…”

Infrared detector characterization for CO 2 DIAL measurement

“…Previous results listed a room temperature multiplication gain of 10-20, with nogain responsivity up to 0.6 A/W 10, 11 . The gain increases by a factor of 5 by cooling the device to liquid nitrogen temperature 10 .…”

Bowtie nanoantenna integrated with indium gallium arsenide antimonide for uncooled infrared detector with enhanced sensitivity

“…This enhances the absorption and provides some limited improvement in the signalto-noise ratio (SNR). It is well known that the performance of conventional IR detectors is limited by the absorption coefficient of the active semiconductor material, and that the performance is improved if the thicker layer of the semiconductor is used for materials with low absorption coefficients [2]. To increase the SNR or sensitivity, antenna-coupled detectors where the antenna is mounted at the boundary between the surrounding media and the active material have been studied [3][4][5][6][7].…”