Using RCA Clean in a Wet Bench Process
Editor’s Note: This article was originally published in May 2015 and has been updated with new information and re-posted in August 2023. The semiconductor manufacturing industry relies heavily on complex and precise processes to create electronic components we rely on every day. One such process is wafer cleaning – an essential step that removes unwanted […]
How Piranha Etch is Used in Silicon Wafer Cleaning
Editor’s Note: This article was originally published in December 2016 and has been updated with additional information and reposted in March 2023. Silicon wafers are fabricated with repeated etching and cleaning steps to produce the micro-structures required for the final silicon semiconductor products. Piranha or SPM (sulfuric peroxide mix) solutions can clean organic material from […]
Why Pre-Diffusion Cleans Are Essential for Silicon Wafer Processing
Silicon wafers must be completely clean before they go through the diffusion process. If contaminating particles are present on the wafer surfaces during the diffusion process, they will cause defects in the final semiconductor product. Pre-diffusion cleaning can be carried out with several methods. RCA clean and Piranha etch use chemicals to strip away wafer […]
How Precise Control of the SPM Process Improves Processing Results
While the SPM (Sulfuric acid Peroxide Mix) or Piranha process quickly removes organic contaminants such as photoresist, it is difficult to control. The cleaning action depends on both the temperature and the concentration of the mixture. Both vary if the process is left to carry on without intervention. Better controls can improve cleaning performance, reliability, […]
How the Piranha Etch Process Improves Silicon Wafer Cleaning
While the Piranha solution quickly removes organic residue from silicon wafers, the process is difficult to control and may produce explosive gas mixtures. The Piranha solution is made up of one part hydrogen peroxide and three parts sulfuric acid, although the ratio may vary for specific applications. The mixture is exothermic and the heat released […]
How Megasonic Cleaning Improves Silicon Wafer Manufacturing
When silicon wafers are cleaned between manufacturing steps, it is critical to remove all contamination from the wafer surfaces. The remaining traces of process chemicals or microscopic particles can disrupt the etching process and result in defective or low-quality semiconductor devices. Megasonic cleaning uses high-frequency sound waves in the cleaning tank to remove contaminants and […]
How Specialized Equipment Improves Wafer Cleaning Results
When equipment is specially designed for a specific cleaning process, residue and particle removal from wafers can be improved. A better wafer cleaning process reduces semiconductor defects and can result in improved output quality. Specialized equipment can clean more quickly, allowing higher facility throughput. Specialized and customized equipment can be adapted for batch processing, continuous […]
Improving Standard Clean Particle Removal in a Wet Bench Process
When silicon wafer yields are not improved with the Standard Clean process, improved particle removal can be achieved with advanced processing equipment. Standard Clean or RCA clean was developed by the RCA company in 1965 and it has changed little since then. It has always been successful in cleaning wafers and removing most particles. However, […]
The Importance of Pre-Diffusion Cleans in Silicon Wafer Cleaning
When wafer cleaning immediately prior to diffusion is effective, semiconductor manufacturing output is of high quality and the defect rate is reduced. A major pre-occupation of pre-diffusion cleaning is the removal of microscopic particles from the surface of the silicon wafer. Particles can prevent even diffusion and may themselves be diffused into the silicon, causing […]
How Innovative Changes to the SPM Process Improves Results
When the SPM process requires frequent spiking with hydrogen peroxide, precise control is difficult and the useful lifetime of the mixture is reduced. The SPM process, using a mixture of sulfuric acid and hydrogen peroxide, is a popular wafer cleaning process because it quickly removes large amounts of organic material from the surface of silicon wafers. It […]