Surface cleaning is oftentimes required to remove organic contaminants and prepare surfaces for subsequent processing. This article discusses the benefits of plasma cleaning, its applications, and some processing guidelines when using our plasma instruments.
For references citing the use of our plasma cleaners, categorized by research application, visit our Technical Library.
Benefits of Plasma Cleaning
- AFM cantilever tips for surface morphology and frictional force measurements
- Glass and semiconductor wafers prior to subsequent deposition
- Patterned Polydimethylsiloxane (PDMS) substrates for microfluidic device fabrication
- Electron microscopy (EM) grids
- Gold surfaces for self-assembly experiments
- Fibrous polymer scaffolds for cell culturing and tissue engineering
- Carbon nanotubes for use as electrodes
- Quartz crystals for quartz crystal microbalance (QCM) measurements
- Optics and crystals (quartz, Ge, ZnSe) for spectroscopic measurements (ATR-FTIR)
- Nanoparticles plasma-treated to tune particle size and alter surface chemistry
Alternatively, an argon plasma may be preferred for cleaning to minimize further oxidation of surfaces (e.g. metals). Argon plasma cleans by ion bombardment and physical ablation of contaminants off the surface, but does not react with the surface. In some cases, a mixture of Ar/O2 may be used to clean surfaces with a combination of physical ablation with argon and chemical reaction with oxygen.
For applications that are sensitive to potential contamination from trace impurities in borosilicate glass, a quartz chamber is recommended over the standard Pyrex chamber.
Below are suggested process conditions for plasma cleaning in a Harrick Plasma cleaner (some experimentation may be required to determine optimal process conditions).
- Pressure: 500 mTorr to 1 Torr
- RF power: MEDIUM or HIGH
- Process time: 1-3 minutes
- Low RF power may be used to minimize surface roughening; the process time may require adjustment to compensate for the lower power