Cadmium Telluride Films Research Articles

THE CRYSTAL STRUCTURE OF THE BASIC LAYERS OF CADMIUM TELLURIDE IN PLANAR ELEMENTS FOR PROTECTING MICROWAVE EQUIPMENT FROM ELECTROMAGNETIC PULSES

To create the physical basis of the industrial technology of planar protection elements, base layers of cadmium telluride, which were obtained by the method of thermal vacuum evaporation at different substrate temperatures on polycore plates with a molybdenum interlayer, were investigated using the X-ray diffractometric method. Temperature intervals corresponding to a qualitative change in the crystal structure of cadmium telluride films were determined. It is shown that the cadmium telluride films obtained at a substrate temperature that does not exceed 100°C contain only the hexagonal metastable phase, have a predominant orientation in the [002] direction, the level of microdeformation is 0.088 - 0.110, the size of the coherent scattering regions is 15.6 - 21.5 nm. The determined periods of the hexagonal crystal lattice a = 4.586 Å and c = 7.505 Å indicate the presence of significant tensile macrodeformations. An increase in the deposition temperature to 200°C leads to the appearance of a stable cubic phase oriented in the [111] direction along with the metastable hexagonal phase of cadmium telluride. At the same time, the orientation of the hexagonal phase in the [002] direction decreases from GH = 1.74 to GH = 1.45. The appearance of the cubic phase also leads to a decrease in microdeformations and the dimensions of the coherent scattering regions of the hexagonal phase to 0.029 - 0.043 nm and 12.1 - 15.8 nm, respectively. A further increase in the temperature of the substrate leads to the formation of cadmium telluride films in which there is only a stable cubic phase without a preferred orientation. At the same time, an increase in the temperature of the substrate to 300°C leads to a decrease in the macrodeformations of the cubic phase, which is evidenced by the approach of the period of the crystal lattice to the theoretical value: from a = 6.4870 Å to a = 6.4858 Å. Thus, it was experimentally shown that in order to ensure stable initial parameters of protection elements, the production of cadmium telluride films must be carried out at a substrate temperature of 300°C, as this prevents the presence of degradation processes due to the thermodynamically activated transformation of the metastable hexagonal phase into a stable cubic phase.

STUDY OF THE DIFFUSION LENGTH OF NONEQUILIBRIUM CHARGE CARRIERS IN CADMIUM TELLURIDE BASE LAYERS

Thin film samples of cadmium telluride were obtained using thermal vacuum evaporation to study the diffusion length of minority charge carriers. Initial state analysis was conducted through X-ray structural studies of cadmium telluride condensed on glass substrates. The analysis revealed two diffraction reflections corresponding to the crystallographic planes (111) and (333). Calculations showed that the sizes of coherent scattering regions were 93 nm and 56 nm, while microstrain values were determined as 11.6×10−3 and 4.8×10−3, respectively, for these planes. Electron diffraction studies identified the zone axis of the formed film structures as [110]. Additionally, twinning and forming a layered substructure within the cadmium telluride thin films were observed. Microscopic surface studies provided insights into the surface relief, measured at approximately 130 nm, and the polycrystalline grain size, determined to be 1 micrometer. The method of spectral dependence of small-signal surface photovoltage was employed to investigate the electrophysical properties of cadmium telluride thin films. The diffusion length of minority charge carriers was calculated to be 0.45 micrometers, which is half the size of the grain dimensions. Furthermore, the transmittance coefficient of cadmium telluride was examined in the wavelength range of 800–900 nm. The optical bandgap energy was 1.4 eV, slightly lower than the 1.5 eV observed for monocrystalline cadmium telluride. In conclusion, cadmium telluride film structures produced by thermal vacuum evaporation exhibit electrophysical and electrical parameters inferior to monocrystalline cadmium telluride. These characteristics, particularly the low diffusion length of minority carriers and short electrical signal decay times make such film structures suitable for use in devices requiring long-term stability under the influence of time, extreme temperatures, electric fields, and radiation.

Chemically processed CdTe thin films for potential applications in solar cells – Effect of Cu doping

Thin films of cadmium telluride (CdTe) have attained the attention of researchers due to the potential application in solar cells. However, cost-effective fabrication of solar cells based on thin films along with remarkable efficiency and control over optical properties is still a challenging task. This study presents an analysis of the structural, optical and electrical properties of undoped and Cu-doped CdTe thin films fabricated on ITO coated glass substrates using an electrodeposition process with a focus on practical applications. Electrolytes of cadmium (Cd), tellurium (Te) and copper (Cu) are prepared with a low molarity of 0.1 M. Thin films are deposited by keeping current density in the range of 0.12–0.3 mA/cm2. Copper doping is varied (2-10 wt%) for the optimized sample. X-ray diffraction crystallography indicates that both undoped CdTe and Cu-doped CdTe films crystallize into a dominant hexagonal lattice. Direct energy band gap is observed for both undoped and doped conditions. The study revealed a drop in the optical band gap energy to ∼1.46 eV with the increase in doping (Cu) concentration from 2 to 10 wt%. Increase in mobility and conductivity is observed with the increase in current density of the deposited undoped CdTe thin films. Whereas, Cu doping of 6 wt% produced thin films with acceptable mobility and conductivity for the doped samples. Furthermore, photoluminescence (PL) spectroscopy unveiled a multitude of emission peaks encompassing the visible spectrum, arising from the combination of electrons and holes through both direct and indirect recombination processes. Findings of this study suggest that chemically produced CdTe thin films would be suitable for use as low-cost applications pertaining to solar cells.

Influence of the Substrate Material on the Structural Properties of Cadmium Telluride Films

Influence of the Substrate Material on the Structural Properties of Cadmium Telluride Films

INFLUENCE OF THE SUBSTRATE MATERIAL ON THE STRUCTURAL PROPERTIES OF CADMIUM TELLURIDE FILMS

With the use of modernized industrial vacuum installations, a series of test samples of cadmium telluride films was produced by the method of thermal vacuum evaporation on glass substrates without a sublayer of transparent conductive oxide, with a sublayer of conductive oxide, and on molybdenum foil substrates to study the influence of the substrate material on the structural parameters of the test samples. The study of the structure was carried out by the method of X-ray diffractometric analysis, the parameters of the lattice, the sizes of the regions of coherent scattering and the texture coefficient of the film were calculated. Based on the results of research into the structural parameters of samples made on a glass substrate, the presence of a cubic phase of cadmium telluride was established. It is shown that when the temperature of the substrate increases, the texture of the samples increases and the presence of tensile stresses is observed, since the lattice period of the cubic phase is significantly higher than that of the tabular phase. For a sample obtained on a glass substrate with a layer of transparent conductive ITO oxide at a substrate temperature of 200 ОC, the presence of two hexagonal phases H1 and H2 and a cubic phase C was established. The samples obtained on a molybdenum foil substrate contain almost entirely the cubic CdTe phase only in very thin sample no. 1 traces of the hexagonal phase are present. For the first thinnest sample, only one main diffraction peak of the cubic phase is observed, which can be explained by the fact that in the initial stages of the film growth, it grows as a highly textured cubic phase with the possible presence of some hexagonal phase. From the analysis of the obtained results, it can be noted that the samples obtained on the molybdenum substrate have a lattice parameter closest to the table data - 6.482–6.483 Å. The structural differences observed between the studied samples are due to the fact that they have a different preferred orientation, which is most likely due to a change in the sputtering speed

Effect of the Diffusion of Copper Atoms in Polycrystalline CdTe Films Doped with Pb Atoms

The process of diffusion of labeled copper atoms in p-CdTe<Pb> coarse-block films with a columnar grain structure has been studied. The CdTe<Pb> film is a p-type semiconductor, where an increase in the Pb concentration in the composition of the CdTe films increases the resistivity ρ of the structure. When the Pb concentration in CdTe changes from 1018 to 5·1019 cm-3, the hole concentration decreases by more than 3 orders of magnitude at a constant operating level depth of EV + (0.4 ± 0.02) eV. This may indicate that the concentration of acceptor defects, which are formed in the films due to self-compensation upon doping with a PbCd donor, exceeds the number of the latter. Electrical measurements by the Hall method were carried out at a direct current and a temperature of 300 K. As a result, an increase in the temperature of films on a Mo-p-CdTe<Pb> substrate during annealing affects the electrical parameter of charge carrier mobility µ, it decreases significantly. X-ray diffraction analysis showed that on the diffraction patterns of samples of p-CdTe<Pb> films, all available reflections correspond to the CdTe phase and up to х = 0.08 do not contain reflections of impurity phases and have a cubic modification. Based on the results of the calculation, it was established that the low values of the diffusion coefficient of Cu atoms are due to the formation of associates of the A type , which are directly dependent on the concentration of atoms. Diffusion length Ln and lifetime τn of minority current carriers in large-block p-type cadmium telluride films, which can also be controlled by introducing lead atoms into cadmium telluride.

Optimization of flexible thin-film photovoltaic converters based on CdS/CdTe heterosystem for integration with solar thermal collectors

The paper introduces the concept of a photoenergy system based on film photovoltaic converters using the CdS/CdTe heterosystem. The goal is to develop a design solution for a flexible thin-film photovoltaic converter system that can be directly mounted on a heat collector plate, integrating photovoltaic converters with thermal collector systems. The paper highlights the limitations of traditional silicon-based photovoltaic converters and propose using flexible photovoltaic converters based on CdS/CdTe, which have concentrated absorption within the visible range and allow unobstructed flow of long-wave solar radiation for efficient thermal energy generation. The paper discusses the methods of obtaining samples of flexible photovoltaic converter ITO/CdS/CdTe/Cu/Au solar cells, including the deposition of layers on polyimide films, chloride treatment, and annealing processes. Analysed the impact of the “chloride” treatment on the structural and optical characteristics of the base layers and present the overall appearance of the thin-film photovoltaic converter samples. The structural analysis of the cadmium telluride films is conducted using X-ray diffractometry techniques, while the optical properties are investigated using a spectrophotometer. The light-voltage characteristics of the photovoltaic converter samples are measured under illumination conditions, and various output parameters and characteristics of the photovoltaic converter are determined. The authors emphasize the significance of optimizing the performance of the cadmium telluride layer in the flexible photovoltaic converter structure and discuss the variation of technological parameters to enhance efficiency. Paper presents the output parameters and light diode characteristics corresponding to different thickness ranges of the CdS layer. Overall, this paper provides valuable insights into the development of flexible film photovoltaic converters based on the CdS/CdTe heterosystem for integrated photovoltaic and thermal collector systems. The experimental methods and results contribute to the understanding of optimizing the performance of the photovoltaic converters and offer potential applications for autonomous heat supply systems.

Optimization physical properties of CdTe /Si solar cell devices fabricated by vacuum evaporation

We investigated at the optical properties, structural makeup, and morphology of thin films of cadmium telluride (CdTe) with a thickness of 150 nm produced by thermal evaporation over glass. The X-ray diffraction study showed that the films had a crystalline composition, a cubic structure, and a preference for grain formation along the (111) crystallographic direction. The outcomes of the inquiry were used to determine these traits. With the use of thin films of CdTe that were doped with Ag at a concentration of 0.5%, the crystallization orientations of pure CdTe (23.58, 39.02, and 46.22) and CdTe:Ag were both determined by X-ray diffraction. orientations (23.72, 39.21, 46.40) For samples that were pure and those that were doped with silver, the optical band gap shrank by (1.52-1.47) eV (400–1100)nm resulting in a drop in the absorption coefficient. An incident power density of (100 mW/cm2) was used to examine the I-V properties of heterojunctions created by light on a variety of clean and doped materials. In accordance with the X-ray diffraction analysis, the films had a cubic structure and dominated grain growth along the (111) crystallographic direction.

Broadband long-wave infrared high-absorption of active materials through hybrid plasmonic resonance modes

Broadband high absorption of long-wavelength infrared light for rough submicron active material films is quite challenging to achieve. Unlike conventional infrared detection units, with over three-layer complex structures, a three-layer metamaterial with mercury cadmium telluride (MCT) film sandwiched between an Au cuboid array and Au mirror is studied through theory and simulations. The results show that propagated/localized surface plasmon resonance simultaneously contribute to broadband absorption under the TM wave of the absorber, while the Fabry–Perot (FP) cavity resonance causes absorption of the TE wave. As surface plasmon resonance concentrates most of the TM wave on the MCT film, 74% of the incident light energy is absorbed by the submicron thickness MCT film within the 8–12 μm waveband, which is approximately 10 times than that of the rough same thickness MCT film. In addition, by replacing the Au mirror with Au grating, the FP cavity along the y-axis direction was destroyed, and the absorber exhibited excellent polarization-sensitive and incident angle-insensitive properties. For the corresponding conceived metamaterial photodetector, as carrier transit time across the gap between Au cuboid is much less than that of other paths, the Au cuboids simultaneously act as microelectrodes to collect photocarriers generated in the gap. Thus the light absorption and photocarrier collection efficiency are hopefully improved simultaneously. Finally, the density of the Au cuboids is increased by adding the same arranged cuboids perpendicular to the original direction on the top surface or by replacing the cuboids with crisscross, which results in broadband polarization-insensitive high absorption by the absorber.

Observation of Individual (Quantum) Emitters Formed by Different Types of Dislocation Cores in Cadmium Telluride Films

Observation of Individual (Quantum) Emitters Formed by Different Types of Dislocation Cores in Cadmium Telluride Films

Electrical Characterization of Chemically Grown CdS and CdTe Thin Films for Solar Cell Application

Thin films of Cadmium Sulphide (CdS) and Cadmium Telluride (CdTe) have gained a great deal of interest due to their potential applications in solar cells. Deposition of CdS and CdTe thin films were performed on Soda Lime glass and FTO substrate at 400℃ and 300℃ respectively using spray pyrolysis technique. The Hall Effect property was measured for the deposited CdS and CdTe films. These results shows the resistivity and mobility of CdS films deposited at 400℃ were 1.588×104 Ωcm and 5.619×102 cm2/Vs, respectively, The annealed CdTe thin film had a resistivity value of 1.016×104 Ωcm, while the annealed and etched CdTe thin film had a resistivity value of 4.52×104 Ωcm, The resultant films are observed to be good to make a solar cell with CdS as a window layer and CdTe as absorber layer.

Electrical Properties of Cadmium Telluride Films and the Al/CdTe Based Schottky Barrier

It is shown that with an increase in the thickness of cadmium telluride films from 0.4 to 1 μm, the resistivity decreases from 8·108 to 8,1·107 Ohm·cm. It is equivalent to an increase in conductivity from 1,25·10-9 to 1,23·10-8 Ohm-1· cm-1. The resistivity and conductivity change only slightly at thicknesses above 1 μm.
 One broad maximum is observed on the X-ray diffraction pattern at film thicknesses D=0.4 μm. This indicates the imperfection of the crystallites. As the thickness increases to 1 μm, a number of clear reflections with increasing intensity appear on the X-ray diffraction pattern, which is associated with the improvement of the crystal structure of the films.
 The current-voltage characteristic of the Schottky diode is obtained. It is shown that with an increase in the forward displacement, a significant increase in the forward current is observed, as well as a noticeable increase in the reverse current with a reverse displacement. The initial section of the forward characteristic at voltages up to 10 V is linear, which is inherent in Schottky barriers. However, the characteristic becomes non-linear at high voltages.
 The nonlinearity of the current-voltage characteristic of the Schottky barrier in a fairly wide range of applied voltage is related to the grain boundary effect in polycrystalline films. Namely, as the applied voltage increases to a certain value, the density of trap states in the region of the crystallite boundary decreases; holes begin to fill, which is usually observed in semiconductors containing conductive particles in a non-conductive matrix. We used this effect when studying the possibility of manufacturing nuclear radiation detectors with a metal — semiconductor — metal structure.

Amplification of photoelectric injection in the photodiode based on large-grain cadmium telluride films

The results of studies of photoelectric injection amplification in the Al–Al2O3–p-CdTe–Mo structure at high bias voltages for the forward current are presented. It has been shown that the spectral sensitivity reaches its maximum value Sλ = 8.4∙104 A/W, when the diode is illuminated with the “own” light at λ = 450 nm and V = 7 V, while when it is illuminated with the “impurity” light at λ = 950 nm Sλ = 4.3∙104 A/W under the same bias voltage. It has been established that when illuminating the structure with the “own” light, the positive feedback mechanism is realized, and when illuminating with “impurity” light, the parametric amplification mechanism is realized.

ACTIVATION METHOD OF CADMIUM TELLURIDE THIN FILMS FOR CREATION EFFECTIVE SOLAR CELLS

The influence of annealing in freon on the cadmium telluride films crystal structure obtained by closed space sublimation method and the output parameters and light diode characteristics of solar cells based on these films were studied. Annealing of structures was performed at a temperature of 400°С for different times. The studies of the crystal structure were performed by the X-ray diffraction analysis. These studies have shown that the annealing in freon leads to a recrystallization of cadmium telluride films, which reduces microstress. It is evidenced by the lattice period decrease after annealing from а = 6.491 Å to а = 6.488 Å. The study of the influence of annealing in freon on the output parameters and light diode characteristics of solar cells was performed. For this purpose the light current-voltage characteristics of ITO/SnO2/CdS/CdTe structures, annealed for 20‑40 minutes, were studied. It was found that the optimal annealing time in freon is 30 minutes. It is shown that the solar cells based on such films have the highest efficiency in 11.7% after annealing in freon for 30 minutes. A simulation of light diode characteristics influence on the efficiency showed that the solar cells efficiency increase due to the diode saturation current density decrease when the annealing time in freon increases to 30 minutes. When the annealing time increases to 40 minutes the efficiency decrease is associated with a shunt resistance decrease. It is also shown that the pre-irradiation of solar cells in the AM1.5 mode for 20 minutes leads to an additional efficiency increase to 12.2%. According to the simulation results, such efficiency increase is also due to the diode saturation current density decrease.

Effect of implanted copper into 1 μm cadmium telluride thick film by heat treatment for optoelectronics: Structural, optical, and electrical properties

In this study, a cadmium telluride (CdTe) film with a thickness of 1 μm was evaporated onto the glass substrate (at a constant temperature of 150°C) using the evaporation technique. These films were immersed in a Cu(NO3)2 (1 g/1000 mL) solution for 30 minutes to infuse copper onto CdTe film. In addition, the treated film was annealed in vacuum at different temperatures (125°C, 250°C, 375°C, and 500°C) for 30 minutes to allow the copper content to diffuse through CdTe through ion exchange process. (EDAX) defines the initial treatment recipe. Use the XRD pattern to calculate the structure (lattice strain and crystal size) of the pure and processed film. The Swanepoel's method is used to calculate the thickness and refractive index of the film. The energy gap of the film is calculated using experimental measurements of reflection and transmission in the strong absorption region. It is found that as the annealing temperature increases, the band gap decreases from 1.50 V to 1.37 eV. The dielectric constant of the film and the power loss function (VELF and SELF) are determined with the annealing temperature increases. Then the electrical properties were studied by the Hall effect, where it was found that the CdTe:Cu film corresponds to the p-type semiconductor. With the increase in annealing temperature, it was found that the resistance decreased from 133.9 × 10−4 to 18.5 × 10−4 Ω cm and the carriers concentration was reduced from 46.7 × 1018 to 23.3 × 1018 cm−3. Moreover, the hall mobility increased from 10 to 146 cm2 V s−1. All these changes of annealed CdTe:Cu films whether optical or electrical, make them candidates for solar cell applications.

Combined experimental and DFT-TDDFT computational, structural and study effect of inter-diffusion Cu into CdTe thick film by annealing for optoelectronics

In the present study, thermal evaporation techniques were used to prepare Cadmium Telluride (CdTe) films with thickness 1 μm on a glass substrate (at constant temperature150 °C). By immersing these films in a solution Cu(NO3)2 (1g/1000ml) for 30 min, the prepared films were doped by ion exchange with Cu. Furthermore, the doped films were annealed in vacuum at different temperatures (25, 125, 250, 375, and 500 °C) for the diffusion of dopant Cu content, for 30 min. Using the method of Swanepoel, the film thickness as well as the refractive index of films was identified. The density functional theory (DFT-TDDFT) by DMol3 was used for the optimization of CdTe and Cu:CdTe as an isolated molecule in the gaseous phase. From using the DMol3/(GGA-PW91) method with DFT-TDDFT simulation, the HOMO and LUMO values for CdTe and Cu:CdTe isolated molecule are 2.41 eV and 1.66 eV, respectively. The MEP computations and Quantum-chemical calculations properties are computed and combined with the experimental study by using DMol3/(GGA-PW91) software. The possible transition in these as deposited and treated films are found to allow direct transition with reduction of the band gap from 1.50 to 1.37 eV with an increase of the temperature of the annealing. Dielectric constant, Energy loss functions (VELF and SELF) for CdTe as deposited and treated were addressed in terms of temperature rise in the annealing. The energy gap is also determined using photoluminescence (PL) and its values the corresponding wavelength peaks correspond roughly to the energy obtained through optical studies.

Comprehensive study of physical properties of cadmium telluride thin films: effect of post-deposition high annealing temperature

Thin films of cadmium telluride (CdTe) with a thickness of 550 nm were prepared using the thermal evaporation method. The resulting films were annealed in air atmosphere at 200 °C, 300 °C, 400 °C and 500 °C. The annealed films were subjected to x-ray diffraction (XRD), micro-Raman spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), ultraviolet-visible spectroscopy and transverse current–voltage (I–V) test analyses to investigate the structural, surface morphological, optical and electrical properties of films, respectively. The XRD patterns reveal the zinc blende structure of the pristine and treated film with the preferred (111) orientation. In addition, the crystallite size increases with the rise in annealing temperature. The Raman spectra reveal a redshift with annealing as well as the formation of Te precipitates in CdTe films. The SEM images show the uniformity and homogeneity of the as-prepared films. The AFM studies show an increase in the surface roughness of the annealed films. The optical energy band gap is found to decrease with the annealing temperature. The I–V measurement indicates the ohmic behavior of CdTe films. The experimental results indicate that the annealed CdTe thin films at 400 °C have optimized physical properties for solar cell applications as an absorber layer.

Structural and optical properties of CdTe + CdTeO3 nanocomposite films with broad blueish photoluminescence

Cadmium telluride plus cadmium tellurite (CdTe + CdTeO3) nanocomposite films were grown by radio frequency magnetron sputtering at room temperature. The CdTe + CdTeO3 samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy, UV–Vis absorption, and room temperature photoluminescence (RTPL). XRD and TEM results indicate that films are composed of CdTe and CdTeO3 nanoparticles (NP’s) with 6.7 ± 0.8 nm and 6 ± 1 nm in size, respectively. CdTe NPs grew in hexagonal wurtzite and cubic zinc blende crystalline phases. CdTeO3 NPs are crystalized in cubic phase. Direct bandgap (Eg) (first discrete electronic transition) calculation indicates Eg = 2.6 ± 0.2 eV for CdTe and 3.3 ± 0.2 eV for CdTeO3. RTPL spectrum evidences a wide signal in the 2.0 to 3.25 eV interval. Results reveal that the emission band maximum, which is centered in the blue region of the visible light, is related with band-to-band transitions in CdTe NPs.

Fabrication of Thin-Film Solar Cells Based on CdTe Films and Investigation of Their Photoelectrical Properties

This study presents the results of investigating thin-film CdS/CdTe-based solar cells obtained on glass substrates with In2O3(Sn) and SnO2 frontal electrodes. On the surface of frontal electrodes (In2O3(Sn)/SnO2), 100-nm thick cadmium sulfide films were deposited by vacuum thermal evaporation at a substrate temperature of 200°C, then application of 4–5-μm thick cadmium telluride films by chemical molecular beam deposition at a substrate temperature of 600°C. The obtained heterosystems were subjected to “chloride” treatment, which is a standard technological operation for the fabrication of efficient solar cells based on CdS/CdTe. Photoelectrical characteristics of the resulting solar cells were studied. An increase in the efficiency of thin-film solar cells after heat treatment was shown.

Photodiodes based on p-on-n junctions formed in MBE-grown n-type MCT absorber layers for the spectral region 8 to 11 μm

Results of measurement of the dark currents and photocurrents of p-on-n photodiodes (PD) formed in In-doped MBE-grown n-type mercury cadmium telluride (MCT) films are reported. We used 3 in. in diameter (0 1 3) GaAs and (0 1 3) Si substrates. The p-on-n junctions were fabricated using the implantation of As+ ions followed by the thermal annealing activation. It was shown that the regime of background-limited performance (BLIP) of the p-on-n PD with experimentally measured long-wave cutoff wavelength (LW) cutoff (λc) of 11.1 and 10.3 μm at 77 K is observed up to elevated temperatures of 105 K and 117 K, respectively. The temperature dependence of the noise equivalent temperature difference (NETD) for p-on-n PD sized 30 × 30 μm was calculated taking into account only PD shot noise. It was shown that such LW p-on-n photodiodes allows to increase the operating temperature of IR FPA detectors up to 100–105 K with the NETD less than 30 mK.