Plasma Technology  

Device: Micromechanical tunable laser - VCSEL (Vertical-Cavity Surface-Emitting Laser)


Application: Low temperature ICP PECVD using temperature sensitive material as
photoresist as the sacrificial layer for deposition of dielectric DBR membranes.

Multi Layer deposition:

11 SiNx – SiOx periods (22 films)
on GaAs with AR- coating
CWL @ 1.53µm
stop bandwidth ~ 340 nm
Reflectivity > 98%

ICP PECVD of SiO and SiN for DBRs



Single Layer deposition
SiNx :
- R.I. @ 632nm = 1.961
- Rdep = 150 Å/min
- stress = 127MPa compressive

SiOx :
- R.I. @ 632nm = 1.466
- Rdep = 189 Å/min
- stress = 27MPa tensil

Plasmalab System 100 with ICP380


ICP Source Design: ESS
All OPT ICP and RF sources are designed
with an “electrostatic shield” (ESS) to
ensure a purely inductive plasma coupling
without a capacitive component.
Therefore contamination by “wall sputtering”
and ion induced substrate damage is excluded.

Source to Substrate distance
This distance can be varied over a wide
range for optimal process control.


With kind permission of
Technische Universität Darmstadt - Optische Nachrichtentechnik,
Prof. Dr. Meissner and
Walter Schottky Institut - Technsiche Universität München,
Prof. Dr. Amann cooperating within EU-project “Subtune” No. 224259

DBR Optimisation:
The stress, refractive index und thickness of the films are varied by
changing the process parameters like the pressure. Then the reflection
& transmission of DBR consisting of SiN / SiO multilayers is measured.

link to homepage email to OPT