Lifetime of semiconductor processing equipment parts can be checked in real time

The Korea Research Institute of Standards and Science (KRISS) has successfully developed a system that diagnoses the lifetime of parts used in the semiconductor plasma processes in real time. It is expected that the new system can help preemptively prevent contaminant particles generated by corrosion of components, thereby upgrading the semiconductor yield as well as the stability and cost efficiency of the process. The work is published in the Journal of the European Ceramic Society.

The plasma process involves precisely etching the surface of a semiconductor substrate or depositing a specific material using a gas ionized into a plasma state. The plasma process is considered a key process directly related to semiconductor yield because the circuit pattern on a semiconductor device must be precisely and uniformly implemented in the plasma process to achieve the performance targeted at the design stage.

Fine contaminant particles generated in the plasma processes have a fatal impact on the process quality. Most contaminant particles are generated when the internal coating parts of process equipment (chambers) are exposed to the plasma environment and corrode. The particles fall on the wafers being processed, generating defective products, and are deposited on the inside the chamber of the equipment , lowering the process performance.

Therefore, it is necessary to diagnose the size and number of particles and predict the lifetime of parts used in the plasma process; however, there was no real-time measurement technology. In most cases, the remaining lifetime of components was indirectly estimated by analyzing the surface of the wafers completely manufactured after the process; although, yield reduction and cost loss occurred due to process defects.

The Emerging Material Metrology Group of KRISS has developed a measurement system that can be attached to plasma process equipment to monitor the status of parts inside the chamber in real time. The system consists of a test sample holder, a capture device, and an analysis sensor.

After attaching a test sample inside the equipment, the film of the component peeled off due to plasma exposure is captured and analyzed by the sensor. The system is capable of analyzing thousands of fine particles of a few micrometers (μm) or less generated during the process, enabling real-time diagnosis of the status and remaining lifespan of the components.

When the newly developed system is applied to manufacturing sites, parts can be replaced in a timely manner before contaminant particles are generated. It is expected that the process stability and productivity can be increased and costs due to unnecessary component replacement can be reduced.

In particular, while it previously took about several days to stop the process, disassemble the equipment, and analyze the components to check their lifespan, the new system allows managers to immediately check it based on the objective data whenever they want, which can also reduce sales losses caused by process discontinuation.

Furthermore, the newly developed system serves as a test bed for semiconductor equipment and component manufacturers in Korea to test the performance of prototypes and obtain official test results.

Principal Researcher Yun, Ju Young of the Emerging Material Metrology Group of KRISS said, “Through the operation of a demonstration test bed, we will increase the reliability and competitiveness of the equipment and components manufactured in Korea and contribute to the localization of semiconductor production processes that are highly dependent on imported equipment.”

This technology is ready for immediate commercialization, and has already been transferred to a semiconductor equipment company and is being used in actual semiconductor production sites.