Process Hierarchy

   Ion Milling
Process characteristics:
Depth
Depth*
must be 0.01 .. 2 µm
0.01 .. 2 µm
Material
Material*
Etch type dry anisotropic
Gas Argon
Mask materials
Materials that can be used to mask etching.
photoresist (G-line), AZ 5214e, photoresist (I-line) (category), AZ 9245, Futurrex NR5-8000, PMMA, Futurrex NR9-8000, AZ 9260
Wafer size
Wafer size
Equipment 4wave ion mill
  • Here are current wafer fixtures available on the tool:
    ---
    1 76.5mm clampless fixture (entire surface of wafer is etched).
    2. 100mm clamped fixture (approx. 2.5 mm clamping on edge of wafer).
    3. 100mm clampless fixture (entire surface of wafer is etched).
    4. 150mm clamped fixture.
    5. 150mm clampless fixture.
Equipment characteristics:
Batch sizes 100 mm: 3, 150 mm: 3, 75 mm: 3
Wafer geometry
Types of wafers this equipment can accept
1-flat, 2-flat, notched, no-flat
Wafer materials
List of wafer materials this tool can accept (not list of all materials, just the wafer itself).
fused silica, silicon carbide, silicon, silicon on insulator, Pyrex (Corning 7740), alumina
Wafer thickness
List or range of wafer thicknesses the tool can accept
200 .. 1000 µm
Comments:
  • The etch rate varies depending on the material.
    Typical rates for common materials are
  • Silicon nitride ~33nm/min
  • Silicon dioxide ~33nm/min
  • gold ~100nm/min