Structure and method for monitoring n-type source-drain injection alignment in cmos

Abstract

The invention provides a monitoring structure and method for N-type source drain injection registration in a CMOS. The monitoring structure comprises a photoresistance region and an N-type source drain ion injection region. The N-type source drain ion injection region is formed by an N-type trap-N-type source drain electrode structure and comprises an N-type trap, an N-type source drain electrode, a grid, a dielectric layer and a contact hole corresponding to the N-type source drain electrode. The photoresistance region is formed by an N-type trap-P-type source drain electrode structure and comprises an N-type trap, a P-type source drain electrode, a grid, a dielectric layer and a contact hole corresponding to the P-type source drain electrode. N-type source drain and P-type source drain are respectively injected into the N-type source drain injection region and the photoresistance region. In voltage contrast images obtained through scanning of negative potential electron beams, the registration of the photoresistance can be monitored according to the changed contact holes, so that the N-type source drain ion injection registration in the CMOS is monitored in real time, and electricity leakage of an PMOS due to the fact that N-type source drain ions are injected into an N-type trap of the PMOS can be avoided.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to a monitoring structure and a monitoring method for monitoring the alignment degree of N-type source-drain injection in CMOS. Background technique [0002] With the development of integrated circuit technology and the scaling down of key dimensions, the process windows of various processes are getting smaller and smaller. CMOS devices have become one of the important electronic components in existing integrated circuits. In the preparation process of CMOS devices, each The requirements of this process are getting higher and higher, such as source-drain implant alignment, etc.; figure 1 As shown, it is a schematic diagram of PMOS leakage defects obtained by electron beam scanning. It is found through research that one of the reasons for the formation of PMOS leakage defects is the alignment deviation during N-type source-drain injection, which leads to the N-type defects in ...

AI Technical Summary

Problems solved by technology

At present, the industry uses optical detection for monitoring, but due to the limitation of resolution and the complexity of alignment deviation in the actual photoresist process, it is difficult to obtain accurate monitoring, and more importantly, the detection results cannot be compared with the resulting Leakage problems to establish direct contact

[0004] Therefore, there is an urgent need for a test structure and method that can accurately monitor the alignment of the N-type source-drain injection in CMOS in real time, so as to avoid the problem that the PMOS device generates leakage and causes the entire device to fail.

Images