Modeling of gallium nitride transistors for high power and high temperature applications

Wide bandgap (WBG) semiconductors such as GaN and SiC are emerging as promising alternatives to Si for new generation of high efficiency power devices. GaN has attracted a lot of attention recently because of its superior material properties leading to potential realization of power transistors for high power, high frequency, and high temperature applications. In order to utilize the full potential of GaN-based power transistors, proper device modeling is essential to verify its operation and improve the design efficiency. In this view, this research work presents modeling and characterization of GaN transistors for high power and high temperature applications. The objective of this research work includes three key areas of GaN device modeling such as physics-based analytical modeling, device simulation with numerical simulator and electrothermal SPICE model for circuit simulation. The analytical model presented in this dissertation enables understanding of the fundamental physics of this newly emerged GaN device technology to improve the operation of existing device structures and to optimize the device configuration in the future. The numerical device simulation allows to verify the analytical model and study the impact of different device parameters. An empirical SPICE model for standard circuit simulator has been developed and presented in the dissertation which allows simulation of power electronic circuits employing GaN power devices. The empirical model provides a good approximation of the device behavior and creates a link between the physics-based analytical model and the actual device testing data. Furthermore, it includes an electrothermal model which can predict the device behavior at elevated temperatures as required for high temperature applications.Includes bibliographical reference

Semiconductor Device Modeling and Simulation for Electronic Circuit Design

This chapter covers different methods of semiconductor device modeling for electronic circuit simulation. It presents a discussion on physics-based analytical modeling approach to predict device operation at specific conditions such as applied bias (e.g., voltages and currents); environment (e.g., temperature, noise); and physical characteristics (e.g., geometry, doping levels). However, formulation of device model involves trade-off between accuracy and computational speed and for most practical operation such as for SPICE-based circuit simulator, empirical modeling approach is often preferred. Thus, this chapter also covers empirical modeling approaches to predict device operation by implementing mathematically fitted equations. In addition, it includes numerical device modeling approaches, which involve numerical device simulation using different types of commercial computer-based tools. Numerical models are used as virtual environment for device optimization under different conditions and the results can be used to validate the simulation models for other operating conditions

Deep Submicron EGFET Based on Transistor Association Technique for Chemical Sensing

Extended-gate field-effect transistor (EGFET) is an electronic interface originally developed as a substitute for an ion-sensitive field-effect transistor (ISFET). Although the literature shows that commercial off-the-shelf components are widely used for biosensor fabrication, studies on electronic interfaces are still scarce (e.g., noise processes, scaling). Therefore, the incorporation of a custom EGFET can lead to biosensors with optimized performance. In this paper, the design and characterization of a transistor association (TA)-based EGFET was investigated. Prototypes were manufactured using a 130 nm standard complementary metal-oxide semiconductor (CMOS) process and compared with devices presented in recent literature. A DC equivalence with the counterpart involving a single equivalent transistor was observed. Experimental results showed a power consumption of 24.99 mW at 1.2 V supply voltage with a minimum die area of 0.685 × 1.2 mm2. The higher aspect ratio devices required a proportionally increased die area and power consumption. Conversely, the input-referred noise showed an opposite trend with a minimum of 176.4 nVrms over the 0.1 to 10 Hz frequency band for a higher aspect ratio. EGFET as a pH sensor presented further validation of the design with an average voltage sensitivity of 50.3 mV/pH, a maximum current sensitivity of 15.71 mA1/2/pH, a linearity higher than 99.9%, and the possibility of operating at a lower noise level with a compact design and a low complexity

EGFET-Based Sensors for Bioanalytical Applications: A Review

Since the 1970s, a great deal of attention has been paid to the development of semiconductor-based biosensors because of the numerous advantages they offer, including high sensitivity, faster response time, miniaturization, and low-cost manufacturing for quick biospecific analysis with reusable features. Commercial biosensors have become highly desirable in the fields of medicine, food, and environmental monitoring as well as military applications, whereas increasing concerns about food safety and health issues have resulted in the introduction of novel legislative standards for these sensors. Numerous devices have been developed for monitoring biological processes such as nucleic acid hybridization, protein⁻protein interaction, antigen⁻antibody bonds, and substrate⁻enzyme reactions, just to name a few. Since the 1980s, scientific interest moved to the development of semiconductor-based devices, which also include integrated front-end electronics, such as the extended-gate field-effect transistor (EGFET) biosensor, one of the first miniaturized chemical sensors. This work is intended to be a review of the state of the art focused on the development of biosensors and chemosensors based on extended-gate field-effect transistor within the field of bioanalytical applications, which will highlight the most recent research reported in the literature. Moreover, a comparison among the diverse EGFET devices will be presented, giving particular attention to the materials and technologies