SC1 cleaning (Standard Clean 1) is a key process step in semiconductor manufacturing for removing particles and organic contaminants from wafer surfaces. Reliable cleaning performance and long-term process stability depend strongly on the accurate chemical composition of the SC1 solution, typically consisting of NH₄OH, H₂O₂, and DI water. Even minor deviations from the defined target concentration can result in fluctuating process performance, increased chemical consumption, and undesired effects on wafer surface quality.
This presentation introduces an on-demand inline mixing concept for SC1 generation based on a DI-water-controlled pressure and flow approach. The individual chemical components are dosed by flow-controlled Levitronix pumps, allowing precise adjustment of the volume flows and therefore the required mixing ratio. A central objective of the system is to ensure that the generated SC1 mixture consistently reaches the defined target concentration before entering the central supply loop, from which multiple wet cleaning tools are continuously supplied.

Compared with conventional batch preparation and large-volume storage tanks, inline mixing enables demand-based chemical generation directly according to process requirements. This reduces chemical overproduction, minimizes disposal caused by limited shelf life or expired storage times, and supports improved sustainability and cost efficiency.

The talk focuses on the technical and process-related requirements for implementing such a system in an industrial semiconductor environment. Key aspects include pressure and flow control accuracy, interaction between the individual media streams, mixture stability, response behavior under varying tool demand, and reliable operation of the central supply loop. In addition, typical challenges observed during implementation and operation are discussed, together with suitable technical and
process-based solutions.
The presentation demonstrates how controlled on-demand inline mixing can support stable target concentrations, reproducible cleaning performance, reduced chemical consumption, and reliable wet process operation in advanced semiconductor manufacturing.