ASML is currently finalizing a GSA (General Standard for ASML) for Additive Manufacturing. These standards largely refer back to international standards. With these standards, the machine builder wants to clarify for suppliers what the AM process must comply with. That should lead to less rejection.
Radu Donose and Hessel Maalderink, who manage AM activities at ASML, said this during Mikrocentrum’s AM for Production. Radu Donose once again outlined the reasons for the chip machine manufacturer to move in the direction of 3D metal printing. The accelerations of the wafer stage, the positioning accuracy and the accuracy in terms of temperature variations are such that additive manufacturing is actually the only solution. “We need AM for that. Low mass, high stiffness, better dynamic properties and optimized thermal behavior.”
Three international ASTM standards for suppliers of AM parts
What causes defects?
The problem, however, is that the quality of the AM parts is insufficiently constant. There are several reasons for this, says Hessel Maalderink. The rapid melting of the material and subsequent solidification can lead to different material properties. Internal tensions can arise during cooling. “And during the process, the microstructure of the material is defined. This can cause defects,” says Maalderink. Other causes are also possible. If the heat is not sufficiently dissipated, warping can occur. And ASML has discovered that in some multi-laser machines, the smoke from one of the lasers can interfere with the second, third or fourth laser beam. “The smoke disrupts the optical path of the other lasers, depending on the gas flow.”
Three ASTM standards for three groups of parts
ASML is therefore going to launch a GSA Additive Manufacturing. The standard currently applies specifically to the laser powder bed process, which is most commonly used for the production of AM parts for ASML. In fact, ASML opts for three international standards. The ASTM 52920 standard applies to low critical parts. The second standard, ASTM 52930, applies to more complex parts. An additional check of mechanical properties takes place here. For critical parts, such as the AM parts through which liquids or gases pass, ASML uses the ASTM 52940 standard. For each part, the supplier must make a so-called manufacturing plan that ASML must approve. Has such a plan been approved and a proof of quality follows before production starts. After this, the process is fixed.
In the future also for other AM processes
ASML has just started rolling out these standards to the suppliers of AM parts for feedback. The aim is to achieve zero defects in the long term. Hessel Maalderink said during AM for Production that ASML wants to expand the GSA to other AM processes. LPBF is currently the most widely used AM technology; therefore the focus is on this.