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1

Sub-THz radiation room temperature sensitivity of long-channel silicon field effect transistors

Sizov F., Golenkov A., But D., Sakhno M., Reva V.

Opto-Electronics Review

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2012

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Vol. 20, No. 2

194-199

EN

Room temperature operating n-MOSFETs (n-type metal-oxide silicon field effect transistors) used for registration of sub-THz (sub-terahertz) radiation in the frequency range v = 53-145 GHz are considered. n-MOSFETs were manufactured by 1-µm Si CMOS technology applied to epitaxial Si-layers (d ≈15 µm) deposited on thick Si substrates (d = 640 µm). It was shown that for transistors with the channel width to length ratio W/L = 20/3 µm without any special antennas used for radiation input, the noise equivalent power (NEP) for radiation frequency v ≈76 GHz can reach NEP ∼6x10⁻¹⁰ W/Hz¹/². With estimated frequency dependent antenna effective area Sest for contact wires considered as antennas, the estimated possible noise equivalent power NEPpos for n-MOSFET structures themselves can be from ∼15 to ∼10³ times better in the specral range of v ∼55-78 GHz reaching NEPpos ≈10⁻¹² W/Hz¹/².

2

Terahertz detectors and focal plane arrays

Rogalski A., Sizov F.

Opto-Electronics Review

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2011

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Vol. 19, No. 3

346-404

EN

Terahertz (THz) technology is one of emerging technologies that will change our life. A lot of attractive applications in security, medicine, biology, astronomy, and non-destructive materials testing have been demonstrated already. However, the realization of THz emitters and receivers is a challenge because the frequencies are too high for conventional electronics and the photon energies are too small for classical optics. As a result, THz radiation is resistant to the techniques commonly employed in these well established neighbouring bands. In the paper, issues associated with the development and exploitation of THz radiation detectors and focal plane arrays are discussed. Historical impressive progress in THz detector sensitivity in a period of more than half century is analyzed. More attention is put on the basic physical phenomena and the recent progress in both direct and heterodyne detectors. After short description of general classification of THz detectors, more details concern Schottky barrier diodes, pair braking detectors, hot electron mixers and field-effect transistor detectors, where links between THz devices and modern technologies such as micromachining are underlined. Also, the operational conditions of THz detectors and their upper performance limits are reviewed. Finally, recent advances in novel nanoelectronic materials and technologies are described. It is expected that applications of nanoscale materials and devices will open the door for further performance improvement in THz detectors.

3

THz/sub-THz bolometer based on electron heating in a semiconductor waveguide

Dobrovolsky V., Sizov F.

Opto-Electronics Review

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2010

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Vol. 18, No. 3

250-258

EN

Direct detection THz/sub-THz bolometer is proposed. In it an electromagnetic wave propagates in the bipolar semiconductor waveguide, heats electrons and holes there, and therefore creates their bipolar thermodiffusion flow and, as well as, the electromotive force (emf). The flow causes the carrier excess concentration. Both this concentration and emf are used to get the bolometer response voltage. The bolometer theoretical model is developed. The possibility without cooling or moderate cooling (about 100 K for the Cd₀.₂Hg₀.₈Te bolometers) to get acceptable for applications values of the noise equivalent power is shown. Experimental results confirm the main model conclusions.

4

THz radiation sensors

Sizov F.

Opto-Electronics Review

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2010

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Vol. 18, No. 1

10-36

EN

In the paper, issues associated with the development and exploitation of terahertz (THz) radiation detectors are discussed. The paper is written for those readers who desire an analysis of the latest developments in different type of THz radiation sensors (detectors), which play an increasing role in different areas of human activity (e.g., security, biological, drugs and explosions detection, imaging, astronomy applications, etc.). The basic physical phenomena and the recent progress in both direct and heterodyne detectors are discussed. More details concern Schottky barrier diodes, pair braking detectors, hot electron mixers, and field-effect transistor detectors. Also the operational conditions of THz detectors and their upper performance limits are discussed.

5

Defects in quantum dots of IIB-VI semiconductors

Babentsov V., Sizov F.

Opto-Electronics Review

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2008

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Vol. 16, No. 3

208-225

EN

This review discusses the properties of structural defects in quantum dots of IIB-VI semiconductors. A great part of this knowledge has been developed in the last years and combined with the improvement in passivation technologies has contributed significantly to the nanotechnology. In this review we introduced the main characterization methods which are used for the study of defects in the nanoform of semiconductors, presented a short description of how native defects can influence the emission spectra, underlined the restrictions which the Auger and deep-level defect recombination imposes on the excitonic emission. We also highlighted the importance of the defect passivation associated with efficiency and photostability of devices.