The silicon wafer cleaning process is a key step in the semiconductor manufacturing process. Warinka supports various types of wafer cleaning processes that maintain purity whether you do research or mass production. Cleaning processes supported by Warinka include RCA cleaning, SC1 and SC 2 (standard cleaning 1 and 2), pre-diffusion cleaning, and other cleaning processes including ozone cleaning and Mound cleaning.
The silicon wafer cleaning process is a key step in the semiconductor manufacturing process. Warinka supports various types of wafer cleaning processes that maintain purity whether you do research or mass production. Cleaning processes supported by Warinka include RCA cleaning, SC1 and SC 2 (standard cleaning 1 and 2), pre-diffusion cleaning, and other cleaning processes including ozone cleaning and Mound cleaning.
Purpose of wafer cleaning
The target wafer cleaning process is to remove chemical and particulate impurities without changing or damaging the wafer surface or substrate. The wafer surface must be left unaffected so that roughness, corrosion or pitting can affect the result of the wafer cleaning process. The yield of the silicon wafer is inversely proportional to the defect density (cleanliness and particle number) of the wafer processing. One way to reduce defect density and increase yield is to use an efficient wafer cleaning process to effectively remove particulate contaminants. For smaller semiconductor devices and geometries, the removal of smaller particles from the silicon wafers becomes even more important. Small particles may be difficult to remove because of the strong electrostatic force between the particles and the wafer substrate.
wafer cleaning technology
The chemicals used in standard wafer cleaning have remained largely unchanged over the past 30 years. It is based on an RCA cleaning process using acidic hydrogen peroxide and ammonium hydroxide solutions. While this is the main approach still in use in industry, recent changes have occurred in its implementation and new optimized cleaning technologies, including ozone cleaning and MPS cleaning systems.
Depending on the particular device type, manufacturing an ICC requires hundreds of precise processing steps. Most steps are done as a single process on the complete chip before cutting them into a single chip. Approximately 20% of the steps are the wafer cleaning process, which highlights the importance of wafer cleaning and substrate surface conditioning.
wafer cleaning step
Pre-diffusion cleaning | Create a surface free of metals, microparticles, and organic pollutants. In some cases, the removal of natural oxides or chemical oxides is required |
Metal ion removal and cleaning | Eliminate metal ions that may adversely affect equipment operation |
particle removal cleaning | Use a Megasonic clean chemical or mechanical scrub to remove particles from the surface. |
Clean after etching | The photoresist and polymer left after the etching process were removed. Remove the photoresist and solid residues, including "etched polymers" |
Demembrane cleaning | Silicon nitride etching / stripping, oxide etching / stripping, silicon etching, and metal etching / stripping |
