RCA Clean

RCA cleaning (Radio Corporation of America) was a cleaning method developed in order to remove both organic and ionic contaminants from wafers.

RCA Organic clean (or Standard Clean 1/ SC1) is used to remove organic contaminants from the surface of the wafers. This is the same as the organic clean for pre-furnace clean. The chemical mixture ratio is 1:1:6 H₂O₂:NH₄OH:H₂O, and is heated to 85oC.

RCA Ionic clean (or Standard Clean 2/ SC2) is used to remove metal and ionic contaminants from the surface of the wafers. This is the same as the ionic clean for pre-furnace clean. The chemical mixture ratio is 1:1:5 H₂O₂:HCl:H₂O, and is heated to 85oC.

Processes

The Rise Training Course will go over the chemistry of the RCA clean as well as the procedure.

First Step: Standard Clean 1/ Organic Clean

• 5 parts of deionized water
• 1 part ammonium hydrixide (29% by weight of NH3)
• 1 part H₂O₂ (hydrogen peroxide, 30%)

This clean is done at 85C for around 10 minutes. The base-peroxide mixture is used to remove organic residue form the substrates. The particles are removed by causing the surface particles to repel. This cleaning results in the formation of a thin silicon dioxide layer on substrates.

Second Step (optional): Oxide Strip

Use DI:HF mixtures to remove thin oxide layers. Approximately 15-30 seconds should effectively remove the oxide layer.

• Use 100:1 DI:HF for Silicon Dioxide wafers
• Use 10:1 DI:HF for Silicon wafers

Third Step: Standard Clean 2/ Ionic Clean

• 6 parts of deionized water
• 1 part hydrochloric acid (37% by weight)
• 1 part H₂O₂ (hydrogen peroxide, 30%)

This clean is done at 85C for around 10 minutes. This clean is used to remove the trace metallic or ionic contaminants. Some of these are introduced in the SC-1 cleaning step. A thin passivization layer can form on wafers which can help protect them from subsequent contamination.

Process SOPs

• Please see individual bench SOPs for how to use this process.

• PFC Bench 01 is used for cleaning 4" and 6" wafers prior to furnace processing
• Acid Bench 73 is used for cleaning piece parts on the hot plate - RCA SOP
• RCA Bench 81 is used for cleaning of materials prior to returning to the cleanroom or before returning to CMOS or semi-clean tools

Technical Data Sheet

• There are currently no data sheets for this chemical.

Safety Data Sheet

• See the SDS for Hydrogen peroxide, Ammonium hydroxide, Hydrofluoric acid, and Hydrochloric acid

References

• Other links that are useful