Process for manufacturing floating body dynamic random access memory cell capable of improving data retention ability

Abstract

The invention provides a process for manufacturing a floating body dynamic random access memory cell capable of improving data retention ability. The process comprises the steps of providing a first silicon wafer, and preparing a buried oxide layer on the first silicon wafer; bonding a second silicon wafer on the first silicon wafer, and preparing a silicon-on-insulator silicon wafer; pretreating the silicon-on-insulator silicon wafer before preparing a silicon-on-insulator device, implanting nitrogen ions into the buried oxide layer of the silicon-on-insulator silicon wafer, activating implanted nitrogen ions through an annealing process, and forming dangling bonds between the buried oxide layer and a substrate interface; and preparing the floating body effect memory cell in a P-channel metal oxide semiconductor (PMOS) structure on the treated silicon-on-insulator silicon wafer. The process for manufacturing the floating body dynamic random access memory cell capable of improving the data retention ability is provided through implementation of the technical scheme, so that interface dangling bonds between the buried oxide layer and a substrate are increased, electrons are trapped effectively, and the data retention performance of the floating body effect memory cell in the PMOS structure can be improved.

Description

technical field [0001] The invention relates to the technical field of semiconductor preparation, in particular to a method for manufacturing a floating body dynamic random access memory unit with improved data retention capability. Background technique [0002] With the rapid development of integrated circuit technology, the degree of integration and technology allows more memories to be integrated on-chip. The proportion of embedded memory in the system-on-chip (SoC, System on Chip) area has increased year by year, from an average of 20% of the chip area in 1999 to 60-70% in 2007 and even 90% in 2014. It can be seen that, The advantages and disadvantages of embedded memory will have a greater impact on the chip. Among them, the dynamic random access memory (DRAM, Dynamic Random Access Memory) in the embedded memory has the advantages of fast speed, low power consumption, high density, etc. With the development of embedded dynamic memory technology, large-capacity DRAM has...

AI Technical Summary

Problems solved by technology

This is due to the floating body effect memory cells of the PMOS structure, when writing "1", such as figure 2 As shown, the carriers accumulated in the substrate are electrons 226. Since the effective mass of electrons is much smaller than that of holes, the mobility of electrons is greater than that of holes. Therefore, the electrons accumulated in the substrate are more likely to leak from the source, resulting in Performance degradation of FBC with PMOS structure in terms of data retention

[0005] In order to solve the above problems, it is necessary to improve the ability of FBC with PMOS structure to capture electrons, so that the data retention performance of FBC with PMOS structure can be improved. New method to solve the main problems faced when using FBC with PMOS structure

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