Floating set grid storage unit and its manufacturing method

Abstract

A floating gate memory cell (floating gate memory cell), including a substrate, and the substrate has a drain (drain) and a source (source) and is isolated by a channel (channel); a floating gate, located at above the channel and isolated by a first insulating layer; and a control gate located above the floating gate and isolated by a second insulating layer. By selecting appropriate deposition conditions, at least part of the floating gate is made of a microcrystalline polysilicon material, and has a grain size ranging from about 50 to 500.

Description

technical field [0001] The present invention relates to a floating gate memory cell and its manufacturing method, and in particular to a floating gate memory cell capable of reducing the indeterminate erasing frequency of a transistor and its manufacturing method. Background technique [0002] One type of integrated circuit memory (IC memory) that can store non-volatile information is called erasable programmable read-only memory (erasable programmable ROM, EPROM). This type of memory allows users to write programs, Or erase the program and write again. One type of EPROM is called N-channel metal-oxide-semiconductor field-effect transistor (N-channelMOSFET), as shown in Figures 1 and 2. A floating gate transistor 10 has two gates 12 and 14 made of polysilicon. Generally, polysilicon is deposited at a high temperature of about 520-700°C by low pressure chemical vapor deposition (LPCVD), and silane (SiH 4 ) or disilane (Si 2 h 6 ) for pyrolysis. If polysilicon is deposit...

AI Technical Summary

Problems solved by technology

For example, this kind of indeterminate erasing will cause over erase of the transistor, so that the memory cell (memory cell) is stuck in the "1" state and cannot be read

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