Manufacturing method for mask read only memory device

Abstract

The invention discloses a method of manufacturing masked read-only memories, which includes steps of providing a semiconductor substrate defined with a memory cell region and a peripheral circuit region, forming an undoped gate material layer on the semiconductor substrate, etching the gate material layer to form a gate in required shape, sequentially forming a first silicon oxide layer and a silicon nitride layer on the semiconductor substrate, filling a dielectric layer in the memory cell region, forming a second silicon oxide layer on the semiconductor substrate, performing silicon oxide and silicon nitride etching, removing the silicon nitride layer from the gate of the memory cell region and forming gate sidewalls at the peripheral circuit region, and performing gate doping. Therefore, the method adopts the undoped gate material layer to form the gate, and the technological process is compatible with standard CMOS technique, thereby avoiding logical process incompatibility causedby the preliminarily doped gate material layer.

Description

technical field [0001] The invention relates to a manufacturing method of a semiconductor storage device, in particular to a manufacturing method of a mask read-only memory (MROM). Background technique [0002] Mask read-only memory (MROM) is one of the common types of semiconductor memory, which is widely used in electronic products such as computers. The mask read-only memory is composed of a memory cell array and a peripheral logic circuit. The memory cell array is usually composed of mutually orthogonal bit lines and word lines: the embedded layer is formed in the memory cell area by ion implantation technology, and the bit line can be formed by further heat treatment. Lines, and word lines are usually gate structures, which are formed through photolithography and etching processes; and peripheral logic circuits often include multiple logic transistors. In the existing mask read-only memory manufacturing process, the gate structure of the logic transistor of the periphe...

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Problems solved by technology

In this way, in the mask read-only memory manufacturing process, the problem of selective formation of metal silicide is involved

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