MARKUS HUUHTANEN, Business Development Manager, Vaisala
The ongoing chip shortage has shined a spotlight on the semiconductor fabrication industry. An increased demand, decreased supply and issues from the COVID-19 pandemic have highlighted the importance of semiconductor chips in our daily lives. After all, chips are not just for consumer electronics like smartphones and tablets but are also integral to many automotive, telecom, data communications, aerospace, manufacturing, robotics and other applications that demand electricity. Without integrated circuits, countless sought-after consumer electronics products and even vehicles cannot be made. The shortage has been felt globally — and even though many manufacturers and government agencies are working to meet demand, the gap likely won’t be closed anytime soon.
As the chip shortage continues, the crisis has created considerable price increases and scalping among consumers, and companies across industries are losing billions of dollars in revenue. Semiconductor wafer and microelectronics manufacturers have been particularly strained, leading the charge toward improved efficiency and sustainability at every stage of the semiconductor manufacturing process.
One of the first steps in optimizing a process is understanding where inefficiency occurs, which can only be done with thorough monitoring. Traditionally, information on wet microfabrication processes, such as etching or chemical mechanical planarization, has been based on experience, test wafers and sample-based laboratory measurements. These techniques are often designed to provide baseline measurements over time rather than data that can help decision-makers take action in the moment.
Leveraging refractometers for in-line liquid concentration measurements, however, enables advanced and accurate process control supporting industrial automation.
What is a refractometer?
Refractometers are used to measure substance concentration in liquids. By shining a light through a system of lenses and onto a prism surface, refractometers measure a specific substance’s standard refractive index, or RI, to determine its concentration in a solution. The same technology has been used in quality control of petrochemicals, pharmaceutical manufacturing, and food and beverage applications such as beer production. Liquid concentration measurement with an in-line refractometer can provide real-time data on the concentration of a given substance in a solution without having to take liquid samples.
Today, many organizations utilize refractometers integrated into the process tools to monitor the fabrication chemicals’ concentration in cleanroom environments. Using an in-line refractometer to measure a wet process can unlock many benefits, such as cost savings and sustainability through efficient use of wet chemicals and improved process quality, throughput and yield through reducing defects and eliminating wafer contamination.
In-line refractometry can be used for real-time control to keep chemical composition within limits, as well as a quick and accurate response to address any issues within wet chemical composition before it damages wafers.
The Vaisala Semicon refractometers (formerly K-Patents) are designed to meet the demands of semiconductor applications with their corrosion-resistant wetted parts and optimized temperature measurement. Moreover, the built-in diagnostics give an instant overview of process conditions. Specially designed to fit into a semiconductor process tool or in an ultra-clean cabinet, this refractometer is also immune to measurement error caused by crystals, particles, bubbles and color in solutions, as shown in FIGURE 1, since impurities do not affect the critical angle measurement.
Click here to read the full article in Semiconductor Digest magazine.