To ensure the extremely accurate writing of their EUV-machines, ASML introduced the Grade 1 cleanliness level in their GSA, which stands for Generic Standard of ASML. After an intensive certification process with multiple tests Meilink Precision Cleaning has now officially been released for cleaning to Grade 1 level, starting the 1st of April this year. This makes Innovar one of the very few companies the industry that is qualified for this level.
Particle and molecular cleanliness
Successfully performing the baseline qualification for particle and molecular cleanliness requires a demonstrated capability to achieve particle cleanliness according to ISO SCP 6. Next to that, it is required that no HIO elements are left on the samples provided for the examination. HIO is short for Hydrogen Induced Outgassing. This outgassing is induced by the EUV-light bundles, but HIO elements such as led, zinc, magnesium or phosphorus are harmful to the optical parts of the EUV-machines. Therefore, we are required to clean and qualify outgassing below an absolute minimum.
Grade 1 in practise
Meeting Grade 1 level at all times requires specific handling, such always working with 2 people, according to a buddy system, and changing gloves even more than with Grade 2. But one of the most demanding requirements is that the Grade 1 surface cannot be touched throughout the whole process. Even any handling directly above Grade 1 surface after cleaning must be avoided as it is a potential risk for cross contamination with undesired particles. Another challenge is that the packaging may not touch the surface. So we need special tooling to keep the bag (clean assy) away from the Grade 1 surface. No tooling simply means no cleaning, at least at Grade 1 level.
Grade 1 for the Brainport Region
Manager Operations at Meilink Precision Cleaning, Hans Cools is very happy with the successful release: “We are really proud to have been released by ASML for cleaning at Grade 1 level. This means we can provide Grade 1 cleaning capacity right here in the Brainport area. Instead of having to go abroad, customers can now get this high-end service in Eindhoven. It was an intensive process, but it is quite exceptional because there are only a few CSP’s that can meet the Grade 1 requirements. And we are now one of them!”