Method for regulating threshold voltage of complementary metal oxide semiconductor

Abstract

The invention discloses a method for regulating the threshold voltage of a complementary metal oxide semiconductor. The method mainly comprises that the implantation dosage and the energy of P-type ions are determined according the threshold value VTP of P-type metal oxide semiconductor, and P-type ion common implantation is conducted to a silicon wafer with gate oxide layer according to the result of the determination; and the implantation dosage and the energy of N-type ions are determined according to the threshold voltage VTN of N-type metal oxide semiconductor, the implantation dosage and the energy of the P-type ions, and photoetching and N-type ion implantation are conducted to the silicon wafer underwent the P-type ion common implantation according to the result of the determination and a P-well photoglyphy used to conduct P-well photoetching to the silicon wafer. By adopting the technical scheme, the VTP and the VTN can be accurately adjusted and the technological cost is saved.

Description

technical field [0001] The invention belongs to the technical field of semiconductor chip manufacturing technology, and in particular relates to a method for adjusting the threshold voltage of complementary metal oxide semiconductors. Background technique [0002] VT (Threshold Voltage, threshold voltage or turn-on voltage) is the gate voltage required to start a conductive channel between the source S and the drain D, which is for CMOS (Complementary Metal-Oxide Semiconductor, Complementary Metal-Oxide Semiconductor) It is a very important electrical parameter, especially for the currently widely used Metal Gate CMOS (Metal Gate CMOS), the threshold voltage affects the process level. Generally, the more advanced the process, the smaller the threshold voltage required to be achieved. [0003] In the traditional semiconductor chip manufacturing process, there are two main methods of adjusting VT as follows: [0004] The first method is to do one-time implantation of boron io...

AI Technical Summary

Problems solved by technology

This method is suitable for the manufacturing process that product design requires VT, but according to this method, a layer of VTP MASK needs to be added separately. Due to the high production cost of VTP MASK, making VTP MASK alone is not conducive to the reduction of the entire process cost

Moreover, this method cannot meet the manufacturing process that requires a low threshold value for VTN. For example, a product design requires VTN to be 0.8V, VTP to be -0.7V, and Gate oxide (gate oxide) thickness to be 1000 angstroms. According to this requirement, the first time The dose of implanted boron ions should be 0.4E11, because the implant dose is too small and has exceeded the limit of the implanter, so stable production cannot be achieved

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