Silicon Etch Process Solutions

 Etch Performance improvements:

  • Etch rate uniformity
  • Etch rate stability
  • Short bath life
  • DI water concentration
  • KOH (potassium hydroxide) concentration
  • Silicate buildup
  • Bleed and feed
  • Etch end point software control
  • Process time etch algorithm corrections
  • Hardware component life

MEI’s SiEtch is the KOH Solution:

SiEtch Tank Design  – Etch Rate Uniformity

  • Tank and Collar materials and design- Cost and Peformance
  • Nitrogen Injection dispersion plates
  • Best Temperature Control
  • KOH ports w/ flow regulation

SiEtch Concentration Controls – Etch rate stability,  End point control

  • Software controlled KOH spiking algorithm used with the DI loss sensor to maintain KOH concentration
  • Feed and bleed chemical controls
  • KOH spike reservoirs
  • IDX software controls by closed loop feedback
  • In line KOH concentration sensor
  • Concentration control by closed loop sensor feedback

DI Concentration Controls  – Etch rate stability

  • High resolution DI injection controls- consistency
  • DI water flow controllers  – pressure stability
  • Independent water loss sensing – etch rate stability
  • Feed and bleed capability – enhanced tank life, lower costs


IDX  Control Software Advantages For KOH Advanced etch control

  • Process time etch algorithm based on KOH sensor inputIDX Flexware, Automation Control Software,

  • Concentration control silicate correction based on wafer size, qty. processed and duration
  • Etch end point target monitoring
  • Concentration control via in-line KOH sensor
  • Chemical bleed and feed Programmable control
  • Independent DI loss and spike control parameters