Nan Ya Technology Corporation

Infineon Technologies Ag

Teng-Wang Huang

Chung-Yen Chou

Chang-Rong Wu

Kristin Schupke

Hai-Han Hung

Shin-Yu Nieh

Chien-Jung Sun

The invention provides a method for forming a deep trench in a substrate. A sacrificial layer and a liner layer are first used to define the deep trench pattern. The sacrificial layer is then replaced with a silicon glass layer. A thick mask layer includes the silicon glass layer, the liner layer and a silicon nitride layer is formed on the substrate. Through an opening of the thick mask layer, a deep trench is etched into the substrate.

Method for fabricating a deep trench in a substrate

A method for etching Si anisotropically uses a solution containing NHF and HF.

Method of etching silicon anisotropically

The invention provides a method for forming a bottle-shaped trench. A semiconductor substrate having a trench and a pad stack layer formed thereon is provided. A masking layer is then formed in the lower portion of the trench. Plasma nitridation is then performed to form a nitride layer covering the sidewalls of the trench, followed by removing the masking layer to expose the sidewalls of the trench. The lower portion of the trench is then expanded by etching to form a bottle-shaped trench.

Method for forming bottle-shaped trench

Growing community of inventors

Taipei Hsien, Taiwan

Teng-Wang Huang