Method for measuring MOS (metal oxide semiconductor) threshold voltages of CMOS (complementary metal oxide semiconductor) inverter

Abstract

The invention provides a method for measuring MOS (metal oxide semiconductor) threshold voltages of a CMOS (complementary metal oxide semiconductor) inverter and aims to solve the technical problem that an NMOS (N-metal-oxide-semiconductor) threshold voltage and a PMOS (P-metal-oxide-semiconductor) threshold voltage in a packaged CMOS inverter cannot be measured simultaneously in the prior art. The method comprises the following implementing steps: a direct-current voltage and a pulse signal are applied to the CMOS inverter simultaneously; a dual-channel oscilloscope acquires input voltages and output voltages of the CMOS inverter simultaneously; a pulse front edge voltage transmission curve and a pulse back edge voltage transmission curve of the CMOS inverter in one period are drawn; voltage amplification factor differences of each of the pulse front edge voltage transmission curve and the pulse back edge voltage transmission curve under different input voltages are calculated, and a difference curve is obtained; the NMOS threshold voltage Vthn and the PMOS threshold voltage Vthp are obtained. The method is high in measurement efficiency and strong in universality and can be applied to extraction of threshold voltages in digit circuit simulation.

Description

technical field [0001] The invention belongs to the technical field of integrated circuits and relates to a method for measuring the MOS threshold voltage of a CMOS inverter, which can be used for extraction and analysis of the threshold voltage in digital circuit design and simulation. Background technique [0002] An inverter is a circuit that inverts the phase of an input signal by 180 degrees. There are two common inverters, namely a TTL inverter and a CMOS (Complementary Metal Oxide Semiconductor, Complementary Metal Oxide Semiconductor) inverter. The input structure and output structure of the TTL NOT gate are composed of semiconductor transistors and resistors. The CMOS inverter consists of two enhanced MOS (Metal Oxide Semiconductor, Metal Oxide Semiconductor), namely NMOS (N-Metal-Oxide-Semiconductor, N-type Metal Oxide Semiconductor) and PMOS (P-Metal-Oxide-Semiconductor) Semiconductor, P-type Metal Oxide Semiconductor). Compared with TTL inverters, CMOS inverte...

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Problems solved by technology

[0008] The purpose of the present invention is to overcome the deficiencies in the above-mentioned prior art, and provides a method for measuring the MOS threshold voltage of a CMOS inverter, which is used to solve the problem that the prior art cannot simultaneously measure the internal NMOS threshold voltage and PMOS of the packaged CMOS inverter. Technical issues with threshold voltage

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