Structure of embedded flash memory and manufacturing method of embedded flash memory

Abstract

The present invention provides a structure of an embedded flash memory and the manufacturing method of the embedded flash memory. Multiple active regions and multiple virtual active regions which are isolated by a shallow trench isolation structure are formed in a polysilicon device region. Through defining the shallow trench isolation light cover of the polysilicon device region, thus patterned shallow trench isolation photoresists are formed above the virtual active regions and a part of the shallow trench isolation structure, and the active regions and the other part of shallow trench isolation structure are exposed. When the ion implantation is carried out, in order not to influence the performance of a flash memory device, usually the angle of ion implantation is fixed, through adjusting the linewidth of the active regions, the virtual active regions, the shallow trench isolation structure and the patterned shallow trench isolation photoresists, and the distance between the patterned shallow trench isolation photoresists, the secondary repeated implantation of the active regions by the ions is avoided, under the premise of not influencing the flash memory device, the performance of the MPOL device is ensured, at the same time the light mask in forming a WLSP1 can be saved, and the production cost is reduced.

Description

technical field [0001] The invention relates to the field of semiconductor manufacturing, in particular to a structure of an embedded flash memory and a manufacturing method of the embedded flash memory. Background technique [0002] In the current semiconductor industry, integrated circuit products can be mainly divided into three types: analog circuits, digital circuits and digital / analog hybrid circuits, among which storage devices are an important type of digital circuits. In recent years, among storage devices, the development of embedded flash memory (Embedded Flash Memory) is particularly rapid. The main feature of embedded flash memory is that it can keep stored information for a long time without power on; and it has the advantages of high integration, fast access speed, easy erasing and rewriting, etc. field has been widely used. [0003] The polysilicon device (MemoryPoly) can provide a stable fixed current (Fixcurrent) for the embedded flash memory. In order to...

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Problems solved by technology

If the GSTI mask is used for ion implantation according to the existing scheme, and the performance of the flash memory device must be taken into account, the angle and dose of ion implantation cannot be adjusted, which will cause an excessively high threshold voltage of the MPOL device and affect its performance, making WLSP1 The photomask cannot be saved. In the semiconductor manufacturing industry, it is well known that the price of the photomask is very expensive. The manufacturing cost is usually calculated based on the cost of the photomask. Saving a photomask will greatly reduce the production cost

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