Abstract-New Insight on Terahertz Rectification in a Metal–Oxide–Semiconductor Field-Effect Transistor Structure

Fabrizio Palma

https://www.mdpi.com/2079-9292/9/7/1089

The use of a metal–oxide–semiconductor field-effect transistor (MOS-FET) permits the rectification of electromagnetic radiation by employing integrated circuit technology. However, obtaining a high-efficiency rectification device requires the assessment of a physical model capable of providing a qualitative and quantitative explanation of the processes involved. For a long time, high-frequency detection based on MOS technology was explained using plasma wave detection theory. In this paper, we review the rectification mechanism in light of high-frequency numerical simulations, showing features never examined until now. The results achieved substantially change our understanding of terahertz (THz) rectification in semiconductors, and can be interpreted by the model based on the self-mixing process in the device substrate, providing a new and essential tool for designing this type of detector.

Abstract-Terahertz Detection in MOS-FET: A new model by the self-mixing

Fabrizio Palma, Rosario Rao,

https://ieeexplore.ieee.org/document/8510162

High frequency detection based on MOS-FET technology was long justified using a mechanism described by the plasma wave detection theory. In this paper we propose a new model based on the self-mixing process, taking place not in the channel, but in the depleted portion of the transistor body. Hydrodynamic semiconductor equations are solved in the small signal approximation. As a result, we present the dependence of the rectified voltage on the bias gate voltage, which fits carefully several experimental literature results.

Abstract-A Model of High-Frequency Self-Mixing in Double-Barrier Rectifier

Fabrizio Palma, R. Rao

https://link.springer.com/article/10.1007/s10762-018-0476-4

In this paper, a new model of the frequency dependence of the double-barrier THz rectifier is presented. The new structure is of interest because it can be realized by CMOS image sensor technology. Its application in a complex field such as that of THz receivers requires the availability of an analytical model, which is reliable and able to highlight the dependence on the parameters of the physical structure. The model is based on the hydrodynamic semiconductor equations, solved in the small signal approximation. The model depicts the mechanisms of the THz modulation of the charge in the depleted regions of the double-barrier device and explains the self-mixing process, the frequency dependence, and the detection capability of the structure. The model thus substantially improves the analytical models of the THz rectification available in literature, mainly based on lamped equivalent circuits.

Abstract-Analytical Model of Double Barrier THz Rectifier

Fabrizio Palma,  OrcID,  Rosario Rao

http://www.mdpi.com/2504-3900/1/4/279

The application of the new structure to the complex field of THz receivers requires the availability of an analytical model, reliable and able to highlight the dependence on the parameters of the physical structure. We present a model of the rectification capability of the double barrier Terahertz radiation (THz) detector, a CMOS compatible structurer. The model is based on the hydrodynamic semiconductor equations; solved in the small signal approximation. The model highlights the high frequency dynamics of carriers in the structure; and furnishes new insight on the origin of the self-mixing rectification process.

Abstract-CMOS Technology Integrated Terahertz Rectifier

Rosario Rao, Giovanni De Amicis, Andrea Del Monte, Fabrizio Palma,

http://www.mdpi.com/2504-3900/1/4/344

We present new developments of CMOS compatible direct conversion terahertz detector operating at room temperature. The rectenna consists of an integrated antenna, realized on the surface of the integrated circuit and connected to a nanometric metallic whisker at one of its edges. The rectifying device can be obtained introducing just minor modifications of the charge storage well in conventional CMOS active pixel image sensor devices, making the proposed solution easy to integrate with existing imaging systems. In the paper we present technological developments of the rectifier structure, realized with minor changes from a standard 0.15 µm technology node. We also present the study of a patch antenna which can be directly integrated on the chip.