Correction method of sheet resistance in ohmic contact area

Abstract

The invention discloses a method for testing and correcting the square resistance of the ohmic contact area, which mainly solves the problem of the square resistance R of the ohmic contact area in the prior art. shc Calculation is not accurate, and the calculation process is complicated. The implementation plan is: make two groups of circular ohmic contact test patterns with similar structures, each group contains a circular ohmic electrode and two concentric circular ohmic electrodes; then test the total resistance of the two groups of circular test patterns; Using this modified formula, the active area sheet resistance R sh Correct the value, and then accurately calculate the square resistance R of the ohmic contact area shc value. The invention has the advantages of simple and easy production of test patterns, simple calculation and accurate results, and can be used for process detection and performance evaluation of semiconductor devices.

Description

technical field [0001] The invention belongs to the technical field of testing, and in particular relates to a method for correcting the square resistance of an ohmic contact area, which can be used in the preparation, performance evaluation and reliability analysis of heterojunction transistors. Background technique [0002] Wide-bandgap semiconductor materials represented by III-V materials have many advantages, and their development has been quite rapid in recent years. Semiconductor devices made of this type of material have excellent advantages such as high electron mobility, wide band gap, high thermal conductivity, high pressure resistance, high temperature resistance, and radiation resistance, and can be widely used in high temperature, high power, optoelectronics, high frequency microwave and mm Wave and other fields have a broad market. Therefore, in recent years, this type of related devices has become a research hotspot both at home and abroad. [0003] In the ...

AI Technical Summary

Problems solved by technology

There are several problems in this method: firstly, since complex processes such as metal deposition and high-temperature annealing are implemented on the ohmic contact area, the sheet resistance of the active area and the ohmic contact area are not equal, or even very different. It cannot be approximated; secondly, the rectangular transmission line model has fringe current effects, so the use of this model has a certain impact on the accuracy of the square resistance value in the ohmic region

There are several problems with this method: first, the traditional CTLM method ignores the sheet resistance of the metal layer during measurement, which will have a certain impact on the experimental results; The difference between the resistance values ​​of these parts is very small, and the error is relatively large after the difference is made; moreover, the formula for directly calculating the square resistance in the ohmic area is more complicated, the amount of calculation is large, and it involves the calculation of trigonometric functions at non-special angles, so the test and The total time for calculation and analysis is long

[0007] With the further development of semiconductor devices, the original ohmic contact area sheet resistance measurement method is becoming more and more difficult to meet the requirements of high-performance semiconductor device development

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