초록 ▼

A method of etching a trench in a silicon layer is disclosed. The silicon layer is disposed below a hard mask layer having a plurality of patterned openings. The etching takes place in a plasma processing chamber. The method includes flowing a first etchant source gas into the plasma processing cham

A method of etching a trench in a silicon layer is disclosed. The silicon layer is disposed below a hard mask layer having a plurality of patterned openings. The etching takes place in a plasma processing chamber. The method includes flowing a first etchant source gas into the plasma processing chamber, forming a first plasma from the first etchant source gas and etching through a first portion of the silicon layer with the first plasma at a first etch rate. The first etch rate being sufficiently slow to form an effective top-rounded attribute in a portion of the trench. The method further includes flowing a second etchant source gas into the plasma processing chamber, forming a second plasma from the second etchant source gas and etching through a second portion of the silicon layer with the second plasma, wherein the etching with the second plasma extends the trench into the silicon layer without unduly damaging the top rounded attribute.

대표청구항 ▼

[ What is claimed is:] [1.]1. In a plasma processing chamber, a method of etching a trench in a silicon layer, said silicon layer being disposed below a hard mask layer, said method comprising:flowing a first etchant source gas into said plasma processing chamber;forming a first plasma from said fir

[ What is claimed is:] [1.]1. In a plasma processing chamber, a method of etching a trench in a silicon layer, said silicon layer being disposed below a hard mask layer, said method comprising:flowing a first etchant source gas into said plasma processing chamber;forming a first plasma from said first etchant source gas;etching through a first portion of said silicon layer with said first plasma to form an effective top-rounded attribute in a portion of said trench;flowing a second etchant source gas into said plasma processing chamber;wherein said first etchant source gas is evacuated from said plasma processing chamber before flowing said second etchant source gas into said plasma processing chamber;forming a second plasma from said second etchant source gas; andetching through a second portion of said silicon layer with said second plasma, wherein said etching with said second plasma extends said trench into said silicon layer without unduly damaging said top rounded attribute.