INNOVATIONS FOR THE FUTURE

The Wafer Handler is the first step in the exposure process, a key part of chip production. It safely and accurately moves wafers, on which chips are built. The module consists of thousands of parts. We develop and produce the most complex ones. We assemble, test and qualify the complete module.

The Wafer Handler delivers precision, speed and reliability without compromising stability. The wafer is positioned with precision twice the width of a human hair. At the end of the process, the temperature varies by only a few thousandths of a degree. Advanced gripping systems transfer the wafer as cleanly as possible and minimise contamination. Did you know that our module makes a new wafer available every 10 seconds?

Even the smallest contaminants can have a major impact on products such as the Wafer Handler. As the module in the chip machine that handles the wafers most, contamination analysis is essential. We investigate how contaminants arise, for example by measuring material wear at both macro and micro levels. 

An example is our Particle Component Test: a unique tool that measures wear at macroscopic level. It enables us to determine how much contamination our modules generate. But that is not all. Using a new calculation model, we simulate the complex deformations that occur at microscopic level when molecular bonds within a material break under excessive loads. This method is more accurate than other calculation models. It also takes material behaviour into account. This research helps us establish design guidelines for, among other things, the gripping systems of the Wafer Handler. We can use these guidelines to design and build cleaner systems.

Increasingly stringent cleanliness requirements pose a major challenge for industry. To guarantee the performance and reliability of products such as the Wafer Handler, we also investigate the flow and deposition of particle contaminants. We analyse and optimise the flow of air and particles in several ways. One method we use is Particle Image Velocimetry (PIV). This optical measurement technique allows us to visualise and analyse flow patterns and turbulence in our designs. 

In our GLOW test setup, we make particle flows visible by blowing smoke-like particles through or around a product with a fan. A laser then illuminates them, allowing us to analyse and calculate the flow using cameras. We can also test how moving parts affect the flow. For example, what happens when a gripping system moves through the space? This helps us make our designs better and more efficient.

The world around us is full of dust and particles that affect our products – and those of our customers –. At VDL ETG, we investigate not only how particles form, flow and settle, but also how to prevent them from reaching critical components. To control contamination at its source, we developed Plasma Seal: an innovative system for sensitive wafer-handling systems. It converts contaminating particles into a gaseous state, gives them an electrical charge and then controls and removes them using electric fields, air flows or gravity. This helps our customers meet their cleanliness requirements more easily.

The Plasma Seal itself also has a unique, clean design. Its motor is located beneath the machine, rather than in the robot arm. The machine also features special magnetic guide wheels that do not touch the robot arm. This prevents dust particles from being released through wear.