Process Hierarchy

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  Silicon DRIE
Process characteristics:
Depth of material removed by etch process
Depth of material removed by etch process, must be 2 .. 50 µm
2 .. 50 µm
Allowed materials photoresist (category), silicon, silicon dioxide
Ambient to which substrate is exposed during processing
Bosch process
Aspect ratio 9
Edge profile
Free form text field for description of edge profile
89 degrees
Etch rate 2 µm/min
Solutions and their concentrations.
Bosch process
Field geometry
Shape of field with dimensions characterized by the maximum field size
Material silicon
Max field size 144 mm
Primary material removal rate divided by removal rates of secondary materials (i.e., factors by which primary material is removed faster than secondary materials)
photoresist (category): 70, silicon: 1
Sides processed either
Uniformity 2
Wafer size
Wafer size
Equipment STS SOI advanced Si etcher
Equipment characteristics:
Batch sizes 100 mm: 1, 150 mm: 1
Wafer geometry
Types of wafers this equipment can accept
1-flat, 2-flat, no-flat, notched
Wafer materials
List of wafer materials this tool can accept (not list of all materials, just the wafer itself).
silicon, silicon on insulator
Wafer thickness
List or range of wafer thicknesses the tool can accept
300 .. 1500 µm
  • Only Silicon is allowed to be exposed.
  • Silicon dioxide can be used as etch stop.
  • 3mm open ring around the wafer is required.
  • Metals are NOT allowed on wafers.
  • Through-wafer etches require additional processing.
  • The uniformity data is for 22um deep etch with <15% open area.
  • Tanner Labs may accept runs with >15% open area, but the uniformity spec would be on best effort basis.