Specific Process Knowledge/Thin film deposition/PECVD

From LabAdviser

PECVD Plasma Enhanced Chemical Vapor Deposition

PECVD1 (part of cluster1)
PECVD3

We have three PECVD's here at DANCHIP. They can all be used to deposit Silicon oxides and Silicon nitrides with or without dopants of Boron, Phosphorus and Germanium. PECVD1 and PECVD3 are used for silicon based processing where as PECVD2 is dedicated deposition on III-V materials. PECVD1 is the cleanest system where as PECVD3 is allowed to use with substrates with small abouts of metal on. See the precise rules in the equipment manuals which are uploaded in LabManager.

PECVD is a chemical vapor deposition process that applies a plasma to enhance chemical reaction rates of reactive spices. PECVD processing allows deposition at lower temperatures, which is often critical in the manufacture of semiconductors.

All though PECVD1, 2 and 3 are very similar you should not expect to transfer a recipe between the systems and get the same exact same result.

Recipes on PECVD1 and PECVD3


A rough overview of the performance of PECVD thin films and some process related parameters

Purpose Deposition of dielectrica
  • Silicon oxide
  • Silicon nitride
  • Silicon oxynitride
  • PBSG (Phosphorous Boron doped Silica Glass)
  • Silicon oxide doped with Germanium
Performance Film thickness
  • ~40nm - 30µm
. Step coverage
  • In general: Not so good
  • PBSG: Floats at 1000oC
. Film quality
  • Not so dense film
  • Hydrogen will be incorporated in the films
Process parameter range Process Temperature
  • 300 oC
. Process pressure
  • 200-900 mTorr
. Gas flows
  • SiHFailed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle _4} :0-60 sccm
  • NHFailed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle _3} :10- sccm
Substrates Batch size
  • 1-3 4" wafer per run
  • 1 6" wafer per run
  • Or several smaler pieces
  • Deposition on one side of the substrate
. Substrate material allowed
  • Silicon wafers
    • with layers of silicon oxide or silicon (oxy)nitride
  • Quartz wafers
. Material allowed on the substrate
  • Aluminium
  • All metals < 5% of the substrate coverage (ONLY PECVD3!)