Process Hierarchy

  Silicon wet etch (TMAH)
Process characteristics:
Depth of material removed by etch process
Depth of material removed by etch process, must be 0 .. 200 µm
0 .. 200 µm
Etch rate 40 nm/min
Solutions and their concentrations.
Mask materials
Materials that can be used to mask etching.
silicon dioxide, photoresist (category)
Material silicon
Primary material removal rate divided by removal rates of secondary materials (i.e., factors by which primary material is removed faster than secondary materials)
silicon: 1
Sides processed both
Temperature 25 °C
Wafer size
Wafer size
Equipment Wet bech #1
Equipment characteristics:
Batch sizes 100 mm: 25, 150 mm: 25
MOS clean yes
Wafer geometry
Types of wafers this equipment can accept
1-flat, 2-flat, notched, no-flat
Wafer holder
Device that holds the wafers during processing.
teflon cassette
Wafer materials
List of wafer materials this tool can accept (not list of all materials, just the wafer itself).
quartz (fused silica), fused silica, silicon, silicon on insulator
Wafer thickness
List or range of wafer thicknesses the tool can accept
300 .. 1000 µm
Extra terms