Three main reasons for a temperature increase in activated p-InAsSbP/n-InAs/n-InAsSbP and p-InAsSbP/ n-InAsSb/n-InAs double heterostructures has been considered, contribution of nonradiative Auger recombination, electron-phonon interaction and Joule heating to diode temperature increase in single element LEDs and flip-chip diode arrays (1x3) were evaluated at forward and reverse bias using data on spatial distribution of the mid-IR radiation intensity and current-voltage characteristics. Keywords: IR LED, IR diode array, Joule heating, Auger recombination, electron-phonon interaction.

This paper examines the thermal resistance of the mid-infrared “flip-chip” LEDs based on the p‑InAsSbP/n-InAsSb heterostructure. It was shown that the measurement of thermal resistance via a thermal control unit (forward p–n junction voltage) for LEDs based on narrow-gap semiconductors must be carried out at low temperature when thermal control unit is constant.

We discuss photoelectrical properties of an on-chip attenuated total reflection (ATR) sensor for the ethanol concentration measurements in an aqueous solution. The on-chip sensor/microchip was made from a p-InAsSbP/n-InAs monolithic double heterostructure with three mesas/individual diodes grown on a single n+-InAs substrate/waveguide. Two heterostructure diodes were used as photodiodes, while the third one - as a LED. The ethanol concentration was measured via an algorithm based on analysis of the I-V characteristic parameters of a photodiode and the L-I characteristics of the LED. Keywords: photodiodes in the mid-IR range, LEDs in the mid-IR range, on-chip sensor, optical sensors, ATR sensor.

This paper focuses on the specific features of an Ohmic contact on undoped n-InAs (n = 2 x 1016 cm-3) that could be used for temperature stabilization and/or temperature reduction in electronic devices, mainly operating in the 3-5 mu m mid-IR range. This feature has been demonstrated in a 100 mu m thick n-InAs slab with three unannealed Cr-Au-Ni-Au contacts formed via evaporation in vacuum. The I-V characteristics showed no deviation from Ohm's law in the temperature range 77-340 K, manifesting a contact resistance ranging from 3.6 x 10-5 to 7.2 x 10-5 Omega cm2 at room temperature. The 2D thermal radiation distribution and the temperature distribution over the n-InAs surface opposite the contact side surface was obtained via a pre-calibrated IR microscope operating at a wavelength of 3 mu m. The measurements revealed a current dependent temperature decline in the area adjacent to the negatively biased contact: at the applied power of 5 mW, cooling as strong as Delta T approximate to 1 K occurred at an ambient temperature of 340 K. The results show potential for the fabrication of heterostructures with a "built-in" cooler that is monolithically integrated with another electronic device.

Photodetectors based on diode heterostracture with InAsSbx photosensitive region (x = 0.38) with long-wave cut-off λ0.1 about 10 μm (296 K) are investigated. The dependences of dark current density and detectivity in the temperature range of 200–425 K have been investigated. It is shown that the experimental samples are characterized by values of dark current density about 500 A/cm2 at room temperature, detectivity 1.2 × 109 and 5 × 109 cm Hz1/2 W–1 at room temperature and 250 K, respectively, and diffusion mechanism of current flow in the temperature range 200–350 K.

2D thermal radiation distribution together with I-V and L-I characteristics has been measured and analyzed in forward and reverse biased p-n heterostructures based on InAs0.9Sb0.1 and grown onto n-InAs substrates. The measurements revealed a sufficient difference in the temperature distribution onto the sample surface at forward and reverse bias, which is explained by an impact of heat pump operation initiated by an electron-phonon interaction at the p-n junction and diode contacts at U < 0.

Three main reasons for a temperature increase in activated p-InAsSbP/n-InAs/n-InAsSbP and p-InAsSbP/n-InAsSb/n-InAs double heterostructures has been considered. Contribution of nonradiative Auger recombination, electron-phonon interaction and Joule heating to diode temperature increase in single element LEDs and flip-chip diode arrays (1×3) were evaluated at forward and reverse bias using data on spatial distribution of the mid-IR radiation intensity and current-voltage characteristics.

The paper presents temperature distribution analysis in activated on-chip chemical sensor based on p-InAsSbP/n-InAsSb/n-InAs 1x3 diode array. Temperature distributions were obtained both experimentally with the use of infrared microscopy, by I-V characteristic analysis and by finite element modelling. The simulated temperature values are in reasonable agreement with experimental data, allowing one to establish a relationship between the temperature of active elements of the sensor. The relationship is important for the improvement of chemical analysis accuracy.

We discuss photoelectrical properties of an on-chip attenuated total reflection (ATR) sensor for the ethanol concentration measurements in an aqueous solution. The on-chip sensor/microchip was made from a p-InAsSbP/n-InAs monolithic double heterostructure with three mesas/individual diodes grown on a single n⁺-InAs substrate/waveguide. Two heterostructure diodes were used as photodiodes, while the third one - as a LED. The ethanol concentration was measured via an algorithm based on analysis of the I–V characteristic parameters of a photodiode and the L–I characteristics of an LED.

I–V and L–I characteristics as well as photocurrent in monolithic p‐InAsSbP/n‐InAs double heterostructure (λ = 3.4 μm) with several mesas/individual diodes grown onto a single n + ‐InAs substrate have been measured at an activation of one of the diodes at ambient temperature in the presence of water, ethanol, and H 2 0 + C 2 H 5 OH mixture at the n + ‐InAs substrate surface. Adequately sufficient photocurrent values, the evidence for the absorption of internally reflected infrared radiation at the n + ‐InAs substrate/liquid interface together with the correlation between the photocurrent and liquid chemical composition indicate the possibility of developing p‐InAsSbP/n‐InAs double heterostructures into a miniature monolithic “on‐chip” evanescent wave sensor of different liquids.

Рассмотрены вольт-амперные характеристики и фототок "монолитных" диодных оптопар, оптически связанных общей для них подложкой из InAs, оценена возможность использования значений фототока для измерения ослабления "исчезающей волны" при полном внутреннем отражении от границы раздела волновод (подложка из InAs)/поглощающее анализируемое вещество. Ключевые слова: оптические сенсоры, датчики химического состава вещества, диодные оптопары, анализаторы МНПВО, анализаторы исчезающей волны, фотодиоды среднего ИК диапазона, светодиоды среднего ИК диапазона.

The current–voltage characteristics and photocurrent of “monolithic” diode optical pairs optically coupled by a substrate made of InAs common for them are considered, and the possibility of using the values of the photocurrent for measuring the attenuation of the “evanescent wave” in the case of total internal reflectance in the waveguide (a substrate made of InAs)/absorbing substance under analysis interphase boundary is evaluated.

Narrow gap heterostructures consisting of two double heterostructures (N-InAsSbP/n-InAs/P-InAsSbP and P-InAsSbP/n-InAs 0.9 Sb 0.1 /N-InAsSbP) grown sequentially onto a n+-InAs substrate and further processed into a two-color photodiode with individual sensing operation at 3.3 and 4 have been studied. Presented and discussed are the photodiode construction details, I-V characteristics as well as sensitivity and detectivity spectra measured at room temperature.

In the present work we fabricated and investigated colloidal Ag nanoparticles (NPs). The NPs were synthesized by the chemical reduction method of Ag 2 SO 4 using NaBH 4 in the presence of different surfactants. Morphological properties of synthesized colloidal Ag-NPs were studied by ultraviolet-visible (UV-vis) spectroscopy and dynamic light scattering (DLS). Average NP size varied in the range from 3 to 15 nm. Redispersibility of dried NPs with various stabilizers was also investigated and recovered that fish oil is effective stabilizer.

N- InAsSbP/InAs /P- InAsSbP double heterostructures have been grown onto n + -InAs substrate and further processed into 2×2 photodiode array containing no n + - InAs. C-V, spectral response as well as mid-IR photoluminescence and electroluminescence in the 77-300 K temperature range have been measured and used for photodiode characterization including D*(λ) and BLIP temperature evaluation.