Infrared photoluminescent light path system for eliminating atmospheric absorption interference and experimental method

Abstract

The invention discloses an infrared photoluminescent light path system for eliminating atmospheric absorption interference and an experimental method. The light path system comprises a Fourier transform infrared spectrum system having a stepping-scanning mode, a pump light system serving as a laser light source, a circuit system achieving electric signal processing and Fourier transform functions, a chopper and phase-locking amplifier for optical signal modulation and demodulation and a broadband infrared source for obtaining an atmospheric absorption reference spectrum. The experimental method for eliminating the influence of atmospheric absorption interference in an infrared photoluminescent spectrum is provided based on the light path system. The light path system facilitates obtaining of real linear signals of the infrared photoluminescent spectrum of a narrow bandgap semiconductor and has the advantages of being easy to operate, high in effective reliability and the like.

Description

Technical field: [0001] The invention relates to an optical path system and an experimental method for eliminating atmospheric absorption interference for infrared photoluminescence (Photoluminescence, PL) testing. Based on the infrared modulation PL technology of the step-sweep Fourier transform infrared (FTIR) spectrometer, combined with the common optical path coupling and dual-channel signal modulation / demodulation extraction separation technology, the traditional single-channel PL method is developed into Dual-channel test technology, so as to realize the reliable elimination of atmospheric absorption interference in infrared PL spectrum. Background technique: [0002] As a classic and effective method for non-destructive testing of materials, PL spectroscopy is widely used in the study of optical properties of materials such as semiconductors and carbon nanotubes. The study of impurities, deep-level defects, etc. has greatly enhanced the understanding of the photoelec...

AI Technical Summary

Problems solved by technology

However, these methods are limited in the application of infrared modulation PL technology

Both the vacuum method and the dry gas purging method need to seal the optical path in a closed space, which is inconvenient for the operation of sample replacement and optical path adjustment. At the same time, the vacuum method requires the support of high-strength hardware, which increases the cost of equipment

More importantly, the mechanical vibration introduced by the vacuuming and purging process reduces the stability of the moving mirror step-scan, which leads to the increase of environmental noise and even makes the infrared modulation PL technology impossible to perform.

On the other hand, the spectral subtraction method requires at least two spectral scans, and is very dependent on the selection of the subtraction factor. In practical applications, this method is difficult to completely eliminate the influence of the environmental transfer function

Images