Memory and method of forming the same

Abstract

A memory and its formation method. The method includes: providing a substrate. The substrate includes an erasure area, a floating gate area and a word line bit line area arranged along a first direction. The floating gate area is located on both sides of the erasure area, and the word line area is arranged along a first direction. The line bit line area is located on both sides of the erase area and the floating gate area; a floating gate structure film and a dielectric layer located on the floating gate structure film are formed on the substrate, and the floating gate area and word line are exposed in the dielectric layer The first opening of the floating gate structure film in the bit line area; forming a first spacer on the sidewall of the first opening; forming a control gate film at the bottom of the first opening; forming a second spacer on the sidewall of the first spacer ; Remove the control gate film and floating gate structure film exposed by the first sidewall, the second sidewall and the dielectric layer to form a floating gate structure layer, a control gate layer and a second opening; remove the dielectric on the erased area layer and a floating gate structure layer to form a third opening and a floating gate structure; an erasure gate structure is formed in the third opening. The method improves memory production efficiency.

Description

technical field [0001] The invention relates to the field of semiconductor manufacturing, in particular to a memory and a forming method thereof. Background technique [0002] Flash memory is an important device in integrated circuit products. The main feature of flash memory is that it can keep stored information for a long time without applying voltage. Flash memory has the advantages of high integration, fast access speed and easy erasing, so it is widely used. [0003] Flash memory is classified into two types: stack gate flash memory and split gate flash memory. The stacked gate flash memory has a floating gate and a control gate above the floating gate. The stacked gate flash memory has the problem of over-erasing. Different from the stacked gate flash memory, the split gate flash memory forms a word line as an erasing gate on one side of the floating gate. The split-gate flash memory can effectively avoid the over-erasing effect. [0004] However, in the prior a...

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Problems solved by technology

[0004] However, in the prior art, multiple patterning processes are required in the formation process of the flash memory, the process is complex, and the production efficiency is low

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