SRAM (Static Random Access Memory) unit structure based on fake contact etch stop layer technology and preparation method of SRAM unit structure

Abstract

The invention discloses a static random access memory (SRAM) unit structure based on a fake contact etch stop layer (CESL) technology and a preparation method of the SRAM unit. In the production process of the SRAM, a tensile liner covers a pull-down transistor of the SRAM and a compressive liner covers a pull-up transistor and a channel transistor of the SRAM. According to the SRAM structure based on the fake CESL technology and the preparation method of the SRAM structure, provided by the invention, a beta value is increased by covering the tensile liner on the pull-down transistor (NMOS (N-channel Metal Oxide Semiconductor) device) and covering the compressive liner on the channel transistor (NMOS device), so that a static noise margin (SNM) is effectively increased and the aim of realizing the stability of the SRAM unit is realized.

Description

technical field [0001] The invention relates to a pseudo-via etching stop layer technology, in particular to a static random access memory (SRAM, Static Random Access Memory) unit structure and a preparation method thereof based on the pseudo-via etching stop layer technology. Background technique [0002] Static Random Access Memory (SRAM, Static Random Access Memory) is a very common embedded memory in logic circuits. Due to its high-density mode, the throughput of integrated circuits is largely limited by the performance of embedded memory. Currently, the most common SRAM cell is the 6T structure. [0003] figure 1 It is a static random access memory unit of 6T structure in the prior art, please refer to figure 1 , where PU is a pull-up transistor (Pull Up PMOS), PD is a pull-down transistor (Pull Down NMOS), and PG is a pass transistor (Passing Gate NMOS). The key indicator for considering the stability of a 6T SRAM cell is static noise redundancy Yu (SNM, Static Nois...

AI Technical Summary

Problems solved by technology

[0008] The invention discloses a static random access memory (SRAM, Static Random Access Memory) unit structure and a preparation method based on pseudo-via etch stop layer (CESL, Contact etch stop layer) technology, which is used to solve the problem of existing conventional CESL (Contact etch stop layer) technology does not contribute to the static noise redundancy (SNM, Static Noise Margin) of SRAM

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