Simulation of the Spatial Distribution of the Local Quantum Efficiency and Photoelectric Characteristics of Photodiode-Based Infrared Focal Plane Arrays

The results of calculation of the spatial distribution of the local quantum efficiency over the area of photodiode-based IR focal plane arrays (IR FPA) are presented. The diffusion of photogenerated charge carriers in the absorber layer of the array was calculated by Monte-Carlo simulation. Methods of reducing the amount of necessary calculations based on using the symmetry properties of the array are discussed. Requirements for the photoelectric and design parameters (absorber-layer thickness, chargecarrier diffusion length and optical absorption length in this layer, the ratio of the size of n–p junctions to the geometrical dimensions of the detector pixels) are formulated that ensure the threshold sensitivity and spatial resolution of IR FPAs.     

A study of thermal processes in high-power InGaN/GaN flip-chip LEDs by IR thermal imaging microscopy

Results of an experimental study of temperature fields generated in high-power AlGaInN heterostructure flip-chip light-emitting diodes (LEDs) via their self-heating at high working currents are presented. The method of IR thermal imaging microscopy employed in the study enables a direct measurement of the temperature distribution over the p-n junction area with a high resolution of ∼3 μm at an absolute measurement error of ∼2 K. It is shown that large temperature gradients may arise in high-power LEDs at high excitation levels as a result of current crowding. This effect should be taken into account when designing lightemitting chips and estimating the admissible operation modes. The method of IR thermal imaging microscopy can also reveal microscopic defects giving rise to current leakage channels and impairing device reliability.     

Fast IR spectrograph (0.5–3.0 μm) based on a hybrid 1 × 384 InAs module

A design and parameters of the IR spectrograph based on an MS2004I monochromator-spectrograph and a hybrid microcircuit of a one-dimensional 1 × 384 InAs focal plane array for registration of fast processes (the registration time from 0.2 ms) are presented. The obtained spectral resolution is 0.3 nm/element at a wavelength of 1.7 μm. The wavelength range registered in a fixed position of the diffraction grating at this wavelength is 118 nm.     

Advanced Design of Scanning Infrared Focal Plane Arrays

Modern designs of time delay and integration (TDI) IR linear scanning focal plane arrays (IR FPAs) are analyzed. Advanced designs of linear IR FPAs with increased sensitivity and spatial resolution are proposed. The analysis is based on Monte-Carlo simulation of the diffusion of photogenerated charge carriers in photodiode arrays based on mercury–cadmium–telluride epitaxial layers taking into account the main photoelectric and design parameters of the detectors and optical system.     

Design of special machine-tool attachments

The automated design of special machine-tool attachments for the machining of high-tech parts and assemblies in order-based production is considered theoretically and experimentally. New models and methods are discussed.     

Multielement hybrid IR FPA based on charge-injected devices: Part II. Thermography systems with InAs elements

Results of experimental investigation of thermography systems based on InAs CID elements of line and matrix hybrid modules (a thermal imager and IR microscope) are presented. Owing to a high time stability, in the short-wave IR range, the implemented thermography systems have a temperature resolution of ～(4–8) mK for an effective frame frequency of 1–10 Hz.     

Infrared scanning microscope with high spatial resolution

Technical parameters and possible applications of an infrared scanning microscope with a spatial resolution of up to 3 μm are considered. It is shown that the device works with both array and linear photodetectors. Original PC software was designed to control the scanning process interactively and receive and process images of objects in the infrared range,.