Plasma etching

Technical staff 

Pascal DUBREUIL (IR - Area responsible)

The plasma etching area is made up of: 

  • Six high density plasma etching devices (RIE-ICP) in order to process 4-inch wafers. 
  • Two devices for removing organic polymer (resist) and surface treatment (fictionalization). 

Every RIE-ICP devices have two RF generators (13.56MHz) allowing to control plasma density (RF source) and radicals energy (RF platen). 
The process pressure is controlled during process by a butterfly valve and turbomolecular pumping. 
RIE-ICP allows to investigate a lot of physic-chemical etching process (ICP and CCP mode). 

The STS (multiplex) equipment allows the silicon deep etching by Bosch process. 

The 3 Aviza Technology machines (Omega 201) allow to process batches of 25 wafers (6-inch). Materials etched are silicon (oxide, nitride…), III-V materials and materials used for micro and nanotechnology. 

The Alcatel (AMS4200) equipment contains 2 reactors, one for the deep etching silicon by tri-pulsed process, and the other for dielectric materials (etching like glass, fused silica, quartz) by continuous etching process. 

The Diener (nano) equipment allows the oxygen treatment of materials used for MOS technology. 

The etching monitoring is made by optical end point detection systems: 

  • LEPD: Laser End Point Detection 
  • OES: Optical Emission Spectroscopy. This system multi wavelength can control the reactor cleanliness. 
  • Probe Zscan: Impedance detection of etching plasma allows etching monitoring and control the reactor cleanliness. 
  • LEPD and OES detections systems can be installed on all etching equipments. 



STS Multiplex 


Aviza Technology Omega 201 



Aviza Technology Omega 201 



Aviza Technology Omega 201 



Tepla 300 



Diener nano



ClusterAMS4200 : 
Si reactor 

Silica reactor 



Detection tools 

Z scan probe : 

End point detection by plasma impedance: 

Reflectometry (Intellemetrix ) : 
End point detection by Laser reflectrometry 670nm 

Plasmascope (Horiba Jobin Yvon) : 
End point detection and control the reactor cleanliness by OES (Optical Emission Spectroscopy) : 
Gamme 190nm-870nm 



Know How 

Bosch process (STS) for the achievement of micrometrical silicon etching with vertical sidewalls 


Tripulse (Alcatel) process for the vias etching achievement 



Etching process with high aspect ratio for the silicon pillar realization 



Standard process with CHF3 chemical for the multi-layers etching (poly-Si, SiNx, SiO2)



VCSEL structures after etching 



Chloride etching process for the 2D photonics crystals in GaAlAs/GaA realization