Two-Channel Detecting Sensor with Signal Cross-Correlation for FTIR Instruments

Abstract

This paper’s purpose was to demonstrate a performance of a novel approach in a low-noise optical sensor for an FTIR spectrometer. Methods: Compared to the standard FTIR detection setup, our sensor ensures a higher signal-to-noise ratio (SNR) and lower signal standard deviation by reducing the uncorrelated noise components (e.g., thermal and 1/f noises of the detection module). Its construction is based on two-channel detection modules and a processing unit with implemented cross-correlation signal analyses. Each module was built of LWIR HgCdTe photodiodes and low-noise transimpedance amplifiers. Results: the experiments demonstrated a decrease in a signal standard deviation of about 1.7 times with a 10 dB-improvement in the SNR. Conclusion: this result indicates our sensor’s main benefit, especially in registered “weak” and noisy interferograms.

Guided CdTe Nanowires Integrated into Fast Near-Infrared Photodetectors

“…Therefore, HgCdTe is often considered the ultimate channel material for devices operating in Fourier transform IR instruments (FTIR). 28 However, both III−V and II−VI semiconductors are usually grown on costly complementary metal-oxide-semiconductor (CMOS)-incompatible substrates that are limited to small areas. In addition, their dark current is relatively high at high temperatures like room temperature, preventing efficient work under such conditions.…”

“…Since some of the materials can be alternatives for the same spectral regimes, one can choose the channel material considering the efficiency of the fabrication process, pricing, and functionality. Therefore, HgCdTe is often considered the ultimate channel material for devices operating in Fourier transform IR instruments (FTIR) . However, both III–V and II–VI semiconductors are usually grown on costly complementary metal-oxide-semiconductor (CMOS)-incompatible substrates that are limited to small areas.…”