Manufacturing method of MIM capacitor and MIM capacitor

Abstract

The invention relates to the field of semiconductors, and provides a manufacturing method of an MIM capacitor and the MIM capacitor. The manufacturing method of the MIM capacitor comprises the following steps: forming a lower polar plate on a substrate; depositing a heat-conducting resistance material with a low temperature coefficient on the lower polar plate to form a first thin-film resistance layer; forming a dielectric layer on the first thin film resistance layer; depositing a heat-conducting resistance material with a low temperature coefficient on the dielectric layer to form a second thin-film resistance layer, and enabling the first thin-film resistance layer and the second thin-film resistance layer to completely wrap the dielectric layer; and forming an upper pole plate on the second thin-film resistance layer. According to the invention, the dielectric layer of the MIM capacitor is totally wrapped by the two film resistance layers with low temperature coefficients, so that the overall temperature coefficient of the MIM capacitor can be reduced, and the temperature linearity performance of the MIM capacitor is improved.

Description

technical field [0001] The present invention relates to the field of semiconductors, in particular to a method for manufacturing an MIM capacitor and a MIM capacitor. Background technique [0002] MIM (metal-insulator-metal, metal-insulator-metal) capacitors have the advantages of high capacitance, low resistivity, and low parasitic effects, and are widely used in radio frequency circuits and high-speed analog circuits. Conventional MIM capacitors are, from top to bottom, an upper plate, a dielectric layer, a lower plate, and metal materials such as aluminum and copper of the lower plate. Usually, the dielectric layer other than the upper plate needs to be etched away, but the etching will cause plasma damage to the dielectric layer, reduce the performance of the capacitor, cause the linearity performance of the capacitor to change with temperature to deteriorate, or cause the reliability of the capacitor to fail. . The poor linearity performance of MIM capacitors with tem...

AI Technical Summary

Problems solved by technology

It is usually necessary to etch away the dielectric layer other than the upper plate, and etching will cause plasma damage to the dielectric layer, which will reduce the performance of the capacitor, resulting in poor linearity of capacitance with temperature, or failure of capacitor reliability.

The linearity performance of MIM capacitors with temperature changes is poor, which greatly restricts the application of MIM capacitors on frequency mixing chips

For example, in the high-precision ADC core capacitor array architecture, a large number of MIM capacitors connected in series and parallel are required. The large temperature coefficient will lead to fluctuations in environmental factors and directly cause differences in the size of the MIM capacitors, which will lead to a significant decrease in the read, write and computing performance of the frequency mixing chip. , so the temperature drift performance (temperature linearity performance) of MIM capacitors needs to be further improved

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