Method for producing COB DRAM bit line for preventing it from collapse

Abstract

The invention relates to a COB-DRAM bit line fabrication method for preventing bit line collapse. This method adopts the "reverse-bitline" (Reverse-Bitline) production method. That is, after the bit line plug metal is formed and the first oxide layer is deposited, the bit line trench is etched, and then the bit line spacer layer is formed, and the barrier layer and the bit line between the bit line metal and the oxide layer are filled. Metal, planarized and etched back to form a bit line, then form a hard mask and deposit a second oxide layer. The advantage of this method is that no matter whether the detection critical dimension of the bit line is too small, the problem of bit line collapse will not occur.

Description

technical field [0001] The invention relates to a manufacturing method of a bit line of a capacitive dynamic random memory (CapacitorOver Bit Line-Dynamic Random Memory, COB-DRAM) in a semiconductor manufacturing process, in particular to a COB-DRAM capable of solving problems such as bit line collapse and destruction bit line fabrication method. Background technique [0002] Due to cost and high operating speed considerations, the size of the device is getting smaller and smaller. Therefore, more challenges are posed to the manufacturing process of integrated circuits. [0003] In the manufacturing process of the current COB-DRAM device, problems often occur in the bit line manufacturing process, such as bit line collapse and damage after bit line etching. As the device size becomes smaller and smaller, this problem will become more and more serious. [0004] For example, the manufacturing method of the bit line in the prior art is as Figure 1A ~ 1C shown. first refere...

AI Technical Summary

Problems solved by technology

[0003] In the current COB-DRAM device manufacturing process, problems often occur in the bit line manufacturing process, such as bit line collapse and damage after bit line etching

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