These models have been widely used in the design and simulation of hgcdte infrared detectors for the development of infrared detector technology. Theoretical performance of mid wavelength hgcdte1 0 0. Itsuno a dissertation submitted in partial ful llment of the requirements for the degree of doctor of philosophy electrical engineering in the university of michigan 2012 doctoral committee. Hgcdte is special since its bandgap depends on the mixture of mercury and cadmium, and the bandgap can be tuned by more than an order of magnitude, from less than 0. Testing detectors and describing their performance 223 6. Absolute linearity measurements on pv hgcdte detectors in. Based on long experience involving photonic technology, hamamatsu provides a wide variety of infrared detectors in order to meet a large range. Status of hgcdte barrier infrared detectors grown by mocvd in military university of technology, journal of electronic materials, 2016, pp. The 1f noise in midwavelength inassb and hgcdte based unipolar barrier infrared detectors, grown on gaas substrate, are studied both experimentally and theoretically. This paper describes the history and current status of hgcdte infrared detector technology at bae systems in lexington, massachusetts, whose corporate legacy includes honeywell 19621991, loral 19911996, and lockheed martin 19962000. Optical study of hgcdte infrared photodetectors using. Thus, based on these advanced hgcdte technologies, we prepare a new generation of cooled high performance ir detectors.
This manual describes major characteristics and applications of hamamatsu infrared detectors, including ingaas pin photodiodes, pbs and pbse photoconductive detectors, inas and insb photovoltaic detectors, mct hgcdte photoconductive detectors, pyroelectric detectors, and hybrid detectors used in a combination of two or more detectors. Hgcdte ir detectors have been intensively developed since the first synthesis of this material in 1958. The center for detectors cfd at the rochester institute of technology rit and raytheon. Infrared ir hybrid detector arrays and discrete detectors operated in the space environment may be subjected to a variety of sources of natural radiation while in orbit. This letisofradirdefir study aims at realizing sub10. The device concept of a specific barrier bandgap architecture integrated with auger suppression is a proper solution for high operating temperature infrared detectors. This means ir detectors intended for applications such as spacebased intelligence, surveillance, and reconnaissance isr or space situational awareness ssa must not only. These devices typically involve a series of layers of di. Hgcdte infrared detectors have been available for half a century. The examination of the dark current reveals three current components.
Lowfrequency noise limitations of inassb, and hgcdtebased. Many physical models of hgcdte infrared detectors, which are based on the basic principles of semiconductor physics, have been developed. Analysis of the temperature dependent hall measurement results indicates the existence of vacancy complexes in the vacancy doped hgcdte epilayers but not in the au. Development of multiband array will continue45 and twoband detectors were demonstrated based on hgcdte fpas610. The future of single to multiband detector technologies. Such devices are still used in current infrared systems. The first generation of infrared detectors made with hgcdte is characterized by a reduced number of pixels and signal processing outside the cryostat. This flexibility demonstration was performed by growing material for. Hgcdte achieves the highest quantum efficiency and lowest dark current of any ir detector material, and the cutoff wavelength of hgcdte can be tuned over a wide range of wavelengths from nir to lwir. Mercury cadmium telluride hgcdte or mct is used in applications where the highest performance ir detectors are required.
Introduction in 1959, a publication by lawson et al 1 triggered the development of variable band gap hg 1. Hgcdte achieves the highest quantum efficiency and lowest dark current of any ir detector material, and the. These wellestablished models are described using widely published. This dissertation involves characterization of hgbased infrared materials for third generation infrared detectors using a wide range of transmission electron microscopy tem techniques.
Among the competitive materials and theoretical predictions favouring typeii superlattices inasgasb, hgcdte has been still considered as the leader in terms of the fundamental physical parameters. Typical dark currents for shortwave infrared hgcdte detectors at cryogenic temperatures are subelectron. In this dissertation, transmission electron microscopy tem was used for the characterization of epitaxial hgcdte epilayers and hgcdtebased devices. Sep 18, 20 this paper presents modeling work carried out using a finiteelement modeling approach. The hgcdte semiconductor alloy system is now firmly established as todays most widely applicable highperformance infrared detector material. Review of the state of infrared detectors for astronomy in. Hgcdte can also detect in the short wave infrared swir atmospheric windows of 2. Characterization of hgcdte and hgcdse materials for third. Large format mbe hgcdte on silicon detector development for. Narrow band gap photon infrared detectors require cryogenic cooling to suppress the noise deteriorating the performance. The honeywell radiation center was founded in 1962 in boston, massachusetts. This article summarizes the fundamental properties of this versatile narrow gap semiconductor, and relates the material properties to its. Photoconductive mercury cadmium telluride detectors.
Hgcdte is a pseudobinary alloy semiconductor that crystallizes in a zinc blendestructure. Abstract hgcdte is the dominant material currently in use for infrared ir focalplanearray fpa technology. Teledynes high performance infrared detectors for space. Although some photoconductive detectors are still used, these are being replaced by photovoltaic devices i. In 1959, lawson and coworkers publication triggered development of variable band gap hg1. A longwavelength infrared lwir hgcdte photodiode fabrication process has been developed based on reactive ion etching rie plasmainduced pton type conversion for junction formation. History of hgcdte infrared detectors at bae systems 2009. In particular, generationrecombination models such as shockleyreadhall through a trap level in a narrow bandgap and auger recombination are included. Pdf recent progress in hgcdte infrared detector technology. This paper summarizes the status of hgcdte infrared detector technology, with emphasis on recent developments in hgcdte photoconductive detector technology for use in first generation thermal imaging. Numerical modeling and optimization of hgcdte infrared. Hgcdte detector arrays utilizing the same multiplexer, or the same family of multiplexers in a larger format, have been or will be employed in other space missions, including the orbiting car bon observatory 2, the wide.
In this dissertation, transmission electron microscopy tem was used for the characterization of epitaxial hgcdte epilayers and hgcdte based devices. This is because of the large spectral range of hgcdte detectors and also the high quantum efficiency. Unipolar superlattice structures based on mbe hgcdte for. History of hgcdte infrared detectors at bae systems. Hgcdtesi materials for long wavelength infrared detectors article pdf available in journal of electronic materials 336. The wavelength response can be varied by adjusting the alloy composition of this ternary compound. Pdf hgcdtesi materials for long wavelength infrared detectors. Hgcdte infrared detectors have been intensively developed over the past forty years since the first synthesis of this compound semiconductor in 1958. Hgcdte augersuppressed infrared detectors under nonequilibrium operation by pierreyves emelie a dissertation submitted in partial fulfillment of the requirements for the degree of doctor of philosophy electrical engineering in the university of michigan 2009 doctoral committee. Status of hgcdte barrier infrared detectors grown by. Hgcdte is a common material in photodetectors of fourier transform infrared spectrometers.
Bandgapengineered hgcdte infrared detector structures for. Teledynes high performance infrared detectors for space missions. Proton irradiation results for longwave hgcdte infrared. Martyniuk institute of applied physics, military university of technology, 2 kaliskiego str. Recently, it was reported that ptype, audoped hgcdte epilayers have a carrier lifetime two to three times higher than the hgvacancy doped epilayers with the same condition type. Status of hgcdte barrier infrared detectors grown by mocvd. Hybrid mosaic hgcdte focal plane arrays have become an important part of advanced infrared detector technology.
Infrared detectors an overview sciencedirect topics. Hgcdte mid and longwave barrier infrared detectors for. To cope with the different diode process issues related to pitch reductionmorphologic realization, shortcircuits, ftm optimization a parametric study was carried out contact size, passivation properties, doping levels, diode processing conditions. Modeling of dark current in hgcdte infrared detectors. Speciality group on infrared detectors and deals with a variety of topics related to infrared detectors, such as pbsnte diodes and detectors, charge coupled devices ccd, photodiodes, and hgcdte photoconductive detectors. This article summarizes the fundamental properties of this versatile narrow gap semiconductor, and relates the material. Improved characterization and evaluation measurements for. Photoconductive mercury cadmium telluride detectors mercury cadmium telluride short form catalog in pdf format j15 series mercury cadmium telluride detectors. Hgcdte based detectors possess higher optical absorption coefficient, quantum efficiency and low thermal generation rate than the extrinsic detectors and silicide schottkybarrier type of devices. Hgcdte is a ternary semiconductor compound which exhibits a wavelength cutoff proportional to the alloy composition.
Hgcdte is a pseudobinary alloy semiconductor that crystallizes in a zinc. Chapter 1 infrared detector characterization over the past several hundreds of years, optical systems telescopes, microscopes, eyeglasses, cameras, etc. Amorphous hgcdte infrared photoconductive detector with high detectivity above 200 k appl. Hgcdte augersuppressed infrared detectors under non. Graduate thesis or dissertation modeling of the orientation dependence of scanned hgcdte infrared detectors. The hgcdte detector is an intrinsic photon detector and absorbs the infrared radiation across the fundamental energy gap. In this chapter, we present the status of hgcdte barrier detectors grown by metalorganic chemical vapor deposition with emphasis on numerical simulations of their properties. Characterization of hgcdte and related materials for third. Keasler2 rochester institute of technology1, raytheon vision systems2 abstract the center for detectors cfd at the rochester institute of technology rit and.
We are developing twolayer lpe ponn hgcdte photovoltaic detector arrays with cutoff wavelengths out to 17. A cross section of the diode structure is shown in figure 1. Discovery of variable band gap hgcdte ternary alloy by lawson and coworkers in 1959 opened a new area in ir detector technology and has provided an unprecedented degree of freedom in infrared. Therefore, the operating temperature of hgcdte based detectors could be higher compared to other types of photon detectors.
So far, the king of infrared detectors has been the hgcdte intrinsic photodetector mct. Extending hgcdte photovoltaic detector technology to. The most commonly used approach for attaching mosaic hgcdte photodiode arrays to their silicon readout multiplexers, both mechanically and electrically, is the use of indium column interconnects2. Technical information sd12 characteristics and use of. The equivalent circuit is a photongenerated current source iph with parallel. Infrared detectors is a collection of papers presented at a meeting of the u. Hgcdte is the most studied semiconductor material for ir detectors and it is the standard against which all of other ir photon detectors are matched against. Results of the evaluation of pv hgcdte detectors in the infrared. The outcome of this fabrication process is a hgcdte array with neartheoretical performance. Bandgapengineered hgcdte infrared detector structures for reduced cooling requirements by anne m. In parallel, the development of dualband infrared detectors has been the core of intense research and technological developments during the last ten years. Hgcdte and quantum well infrared photodetector qwip technology is expanding in singlecolor to multicolor detectors and recently, qwip have demonstrated multicolor detector arrays. Audoped hgcdte for infrared detectors and focal plane arrays. The 1f noise in midwavelength inassb and hgcdtebased unipolar barrier infrared detectors, grown on gaas substrate, are studied both experimentally and theoretically.
The birth of photodetectors dates back to 1873 when smith discovered photoconductivity in selenium. The process has been successfully applied to produce devices. Recent progress in hgcdte infrared detector technology. The ptype side of the diode is produced by as implantation through the capping layer into the ntype base material.
A unique type of infrared detector material is mercurycadmiumtelluride hgcdte, referred to as mercadtel, or mct. Midwave infrared nbn structures based on hgcdte grown by molecular beam epitaxy on gaas 0 substrates were fabricated. But even at cryogenic temperatures, it is still important to quantify dark current as it adds a source of shot noise to acquired signals. In a wide temperature range, the mechanisms of the formation of dark currentvoltage characteristics of fabricated nbn. Each detector is optimized for specified wavebands of. Theocharous theo optical metrology group, npl, uk e. Status of hgcdte barrier infrared detectors grown by mocvd in military university of technology 4565. Infrared detectors infrared detectors are widely used in diverse field including measurement, analysis, industry, communication, agriculture, medicine, physical and chemical science, astronomy and space. Status of hgcdte barrier infrared detectors grown by mocvd in. May 07, 2009 this paper describes the history and current status of hgcdte infrared detector technology at bae systems in lexington, massachusetts, whose corporate legacy includes honeywell 19621991, loral 19911996, and lockheed martin 19962000.
Photovoltaic mercury cadmium telluride detectors photovoltaic mercury cadmium telluride short form catalog in pdf format j19te series photovoltaic mct detectors. Hgcdte longwavelength infrared photovoltaic detectors. The new genera tion of infrared detectors involves large one or two dimensional focal plane arrays. Design methods for hgcdte infrared detectors springerlink. Graduate thesis or dissertation modeling of the orientation. Lwir hgcdte heterostructure with parameters assumed for the growth and modeling. Hence, the hgcdte based detectors possess higher optical absorption coefficient, quantum efficiency and low thermal generation rate than the extrinsic detectors and. We present ponp heterostructure hgcdte photovoltaic device data that illustrate the high performance and flexibility in bandgap control of molecular beam epitaxy technology. Lowfrequency noise limitations of inassb, and hgcdte. Molecular beam epitaxy hgcdte infrared photovoltaic detectors. J19te series detectors are highquality hgcdte photodiodes for use in the 500nm to 5. Absolute linearity measurements on pv hgcdte detectors in the. Today, hgcdte is the most widely used infrared detector material. It is predicted that the pixel size of longwave hgcdte infrared detectors can be reduced to 5 m, while that of midwave hgcdte infrared detectors can be reduced to 3 m.