Reservation  -     

Center of MicroNanoTechnology CMi

Unusual processes

Attention Preliminary and fundamental remark:
  • SAFETY OPERATOR MANUAL TO OPERATE ON CMi WETBENCHES (HERE)

Contents: CMI

  1. Introduction
  2. Hazards
  3. Wetbench description
  4. Used materials
  5. Parameters

I. Introduction CMI

Unusual processes contain not standard wet etchings (occasional) of metals such as Au, Ni, Cu, Cr(selective over/Cu).

II. Hazards CMI

These etching baths are highly toxic.
  • Because the baths are manipulated by Users (filling, draining, disposal), strong attentiveness is highly important to ensure safe operation.
  • It is necessary to be protected against accidental liquid splashes over the body, over the face and more particularly over the eyes.
  • Full chemistry protection is required and a lot of calm in handling things is essential.

III. Wetbench description CMI

wetbench

The wet bench is fitted with:

wetbench

IV. Used materials CMI

Wafers: Si, glass or pyrex
It is highly recommended to first check the etching rate by using a test wafer.
If etch rate is too far from values given below, contact CMi staff.

V. Parameters CMI

Bath Chemistry Proportion Etch rate
Remarks
Au etchKI + I225 g/l and 12 g/l40 - 80 nm/min  
Cr etch(NH4)2Ce(NO3)6 + HClO4 65nm/min CR7
Cr etch selectif sur CuKMnO4 + Na3PO460 g/l and 200 g/l40 nm/min  
Ni etch(NH4)2S2O8 + FeCl391 g/l and 7.3 g/l>100 nm/min
etches Au ~15 nm/min
Cu etch (NH4)2S2O8 + H2SO4 (96%) 60 g/l and 10 ml/l 200 nm/min