Nan Ya Technology Corporation

Shih-Chi Hsu

Tse Yao Huang

Yinan Chen

Hsing-Chuan Tsai

This present invention provides methods for isolating interconnects characterized by first isolating the top and bottom interconnects with an IMD consisting of a traditional low-k dielectric material, then dissolving the low-k material with a suitable solvent and using air or a noble gas instead of the traditional low-k dielectric material to isolate the interconnects.

Methods for isolating interconnects

A method for fabricating a DRAM capacitor is described. First, a semiconductor substrate having a capacitor contact is provided. Next, a first polysilicon layer is formed. Then, an oxide layer and a silicon oxy-nitride layer are sequentially formed over the first polysilicon layer. Next, the silicon oxy-nitride layer, the oxide layer, and the first polysilicon layer are selectively etched to leave a rectangular stack layer. Afterwards, the oxide layer and the first polysilicon layer of the rectangular stack layer are etched from the sidewall direction to leave a double T-shaped stack layer. Then, second polysilicon layer is formed on the upper surface and the sidewall of the double T-shaped stack layer. Next, the second polysilicon layer is selectively removed. The remaining second and first polysilicon layer are used as the bottom electrode. Afterwards, a dielectric layer and an upper electrode are formed on the bottom electrode.

Growing community of inventors

Chung-Li, Taiwan

Shih-Chi Hsu