Part of the Oxford Instruments Group
The next level of SiC surface quality
Plasma Polishing

We are introducing a unique, patented approach to achieve smooth, low defect density SiC substrate surfaces. The Plasma Polishing technique has been proven to achieve sub-nm surface smoothness and enabled low defect density Epitaxial growth on 150mm SiC wafers. 

The SiC substrate surface quality is the starting point affecting the quality of epi, device performance, reliability and lifetime. Achieving an optimal surface is difficult due to the hardness of SiC and the methods used to slice and thin the wafers from the starting boule. Properly conditioning the surface is vital to enable yield and performance down the manufacturing line.

Plasma etching is an established processing technique within front end processing for semiconductor high volume manufacturing. Through patented processes and equipment adaptions, we can provide a comprehensive polishing solution delivering the surface material quality required for silicon carbide devices. 


Unique Benefits

Plasma Polishing technique enables you to:

  • Achieve uniform epi-ready substrate surface.
  • Reduce substrate stress with minimal bow.
  • Run to run stability throughout entire campaign including before and after maintenance and part exchange
  • Reduced cycle time with better productivity

Smooth SiC Wafer Process with Plasma Polishing

SiC substrate surface before polishing
SiC substrate surface before polishing
SiC substrate surface after etch
SiC substrate surface after etch (Plasma Polishing)
SiC substrate surface after epi growth
SiC substrate surface after etch

Plasma processing a standard within front-end-of-line (FEOL)

150mm SiC wafers are standard now and moving to 200mm in the near future. Moving to larger wafers sizes favours single wafer processing over batch processing. This allows industry standard methods of wafer handling, monitoring and control to be applied reducing touch-time, increasing yield and efficiency. The trend within front end processing is for dry, plasma processing to displace wet processes as plasma processing achieves higher repeatability, greater process control and systems more suitable to the fab cleanroom environment.

Wafer grinding and CMP require a series of steps utilizing varying grit to improve the surface quality. This mechanical process causes strain on the substrate increasing breakage and wafer loss. The particles leave scratches on the surface as it scrapes the SiC. Plasma processing uses ionised gas to remove the SiC actively, the ions and molecules are the smallest possible removal medium.

Plasma Polishing replaces the CMP method in SiC process line. 
*Orange processes show solutions covered by Oxford Instruments Plasma Technology.

Reduced Cost of Ownership

Plasma Polishing Costs vs. CPM Costs

Plasma polishing reduces the materials usage costs, running costs and approaches zero wafer breakage levels. On the contrary, consumables and chemical are the biggest cost driver for CMP process.

Plasma Polishing a cleaner, greener solution 

Clean water is recognised as becoming valuable and scarcer on a global scale, it is one of the key environmental issues of our lifetimes.

Plasma processing is standard within semiconductor HVM fabs with well established and controlled methods for handling of exhaust gases to strict environmental standards. The water used for plasma processing is the fab recirculation supply which is constantly recycled and re-used.

CMP requires large amounts of water to dilute and dispose of the slurry and toxic chemical effluent resulting from the process, a large cost and complexity when running large HVM cleanroom facilities.

Plasma Polishing is a greener more cost-effective alternative to CMP.
Plasma Polishing is a greener more cost-effective alternative to CMP

PlasmaPro 100 Polaris ICP


Plasma etching has been proven to provide the high quality substrate finish needed to minimise epi defects and maximise SiC device performance. We have developed an innovative cassette to cassette plasma process solutions which provide the best SiC substrate surface quality.

  • Maintain smooth surface
  • Removal of sub-surface damage layers from sawing and polishing
  • High conductance pumping system 
  • Excellent process repeatability 
  • Established in major substrate production suppliers

Send us your sample and we can process your wafers at our advanced applications facility in the UK. 

PlasmaPro 100 Cobra ICP Etch Cluster - Oxford Instruments

Plasma Polishing Systems