Storage unit manufacturing method and apparatus

Abstract

Depositing an adulterated polycrystalline silicon layer at contact nodes inside storage device and contact zones of bit lines forms an interface with low current leakage. Then, tungsten plug with low contact impedance is formed above the said polycrystalline silicon layer. Thus, the plug of storage in dual layer structure possesses both characters of low current leakage and low contact impedance.

Description

technical field [0001] The present invention relates to a memory manufacturing method and device, in particular to a doped polysilicon layer deposited at the internal contact node of the memory to form a low leakage interface, and then a low contact resistance tungsten plug is formed on the polysilicon layer. The plug constitutes a memory manufacturing method and device for a memory plug having both low leakage current and low contact resistance. technical background [0002] Embedded DRAM (Embeded DRAM) is a kind of DRAM manufactured by integrating memory circuit and logic circuit in the same manufacturing process. However, directly integrating the above two circuits with different characteristics in the same manufacturing process will cause the following problems: as far as the memory circuit part is concerned, the leakage current of the memory cell and the capacitor must be limited to a minimum amount as much as possible, so that the memory can have a relatively high perf...

AI Technical Summary

Problems solved by technology

However, directly integrating the above two circuits with different characteristics in the same manufacturing process will cause the following problems: as far as the memory circuit part is concerned, the leakage current of the memory cell and the capacitor must be limited to a minimum amount as much as possible, so that the memory can have a relatively high performance. long hold time

Therefore, the memory circuit part uses doped polysilicon plugs (Doped poly plug) as the conductive circuit of the memory cell contact area and the bit line contact, providing low leakage junction characteristics, but there is a problem of high contact resistance (Rc)

On the other hand, the logic circuit part of the embedded memory must have a high driving current to have a fast response speed, so the internal conductive circuit is made of tungsten plugs to meet the low contact resistance and high-speed characteristics, but the leakage current is relatively worse

Images