Thermal variation of specific contact resistance

Test structures for the determination of specific contact resistance are an area of continual research and improvement. It is always important to achieve reliable and accurate results in the extraction of any parameter. Several test structures achieve these conditions, of reliability and accuracy, including the Transmission Line Model, the Circular Transmission Line Model and the newer Single Dot test structure. This work seeks to improve the techniques used to extract specific contact resistance with a focus on the Circular Transmission Model and its equations. As such, the mathematical solutions to the Circular Transmission Line model have been reduced such that they are simpler and therefore faster to solve with no loss of accuracy.<br><br>3C-SiC is used as a semiconductor example in developing the work presented. 3C-SiC is not easily etched and is a good example of a semiconductor where circular transmission line model test structures are appropriate. Results presented in this report demonstrated how the improved analysis process increases the accuracy of measurements for determining specific contact resistance.<br><br>The effects of temperature on specific contact resistance are discussed and analytical models developed. Since the pioneering research in this area and the extensive reports that were produced in the 1960s and 1970s, there has been relatively little work reported on investigating and testing of specific contact resistance with regard to changes in temperature. In this thesis similar experimental work is reported but with a unified analytical model for specific contact resistance due to different electron transport mechanisms.<br><br>This work proposes a solution to determining specific contact resistance at all temperature ranges and doping concentrations with the use of one equation, therefore simplifying the process and ρc determination. In addition the proposal is made that when reporting specific contact resistance it should include the temperature that it has been determined at, such that a more complete understanding can be obtained of the parameter.