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LNF_Poly is designed for etching Si and Polysilicon in the LAM 9400. This recipe produces a very vertical sidewall angle and has a high selectively to oxide (~18:1).

About this Process
Process Details
Equipment LAM 9400
Technology RIE
Material Poly
Mask Materials PR
Gases Used HBr, He
Date Created 2016

Contents

Etch Rates

  • Polysilicon - 2340 Å/min (blanket 150mm poly)
  • Si - 2800 Å/min (<10% open area)
  • SPR 220 (3.0) - 275 Å/min
  • SiO2 - 150 Å/min

Parameters

Parameter Breakthrough Main Etch
Time 10 sec variable
Pressure 5 mTorr 30 mTorr
TCP Power 300 W 600 W
Bias Power 100 W 90 W
Cl2 Flow 60 sccm 0 sccm
HBr Flow 0 sccm 100 sccm
He Flow 0 sccm 100 sccm

Sidewall Profile

  • Nearly a 90 degree sidewall angle

Limitations

This process should not be run below 25 mTorr since the tool has difficulty stabilizing a pure HBr process in that pressure regime.