As a corporate spin-off of ASM, the Dutch company Levitech produces machines for the semiconductor industry. To achieve the smaller structures and greater uniformity in semiconductors that the market requires, the machine manufacturer had to implement new heat transfer methods. This requires faster temperature correction and above all more precise control. That is why Levitech looked for an alternative to control thermal processes in their Levitor machine. In JUMO, the company from Almere in the Netherlands found the partner with whom the solution could be implemented.
The reactor for wafer manufacturing consists of 2 graphite disks that are heated to the appropriate process temperature. To generate optimum results, the disks need to exhibit specific features. Gas is used during this process to cause the wafer to hover between both disks without touching them. To achieve the necessary temperature of 1 200 degrees Celsius, special Kanthal® heating elements are used.
The goal was to apply innovative methods for heat transfer which allow to facilitate very fast heating of the wafer and also very fast cooling. Both sides of the wafer have a uniform opening of 0.15 millimeters to ensure extremely efficient thermal conductivity. The wafer is heated to the temperature of the graphite disks within seconds. These are controlled with a specific heating control system.
The heating control system is where the thyristor power controller from JUMO comes into play. The JUMO TYA 201 controls the required current and voltage of the Kanthal® heating element in every temperature phase and thereby ensures precise temperature progression during the process. This system enables the wafers to be produced at an optimum temperature that is the same every time.
Thanks to the characteristics of the JUMO TYA 201 thyristor power controller, the requirement for more precise control and faster temperature correction could be met. As a result, the innovative methods of heat transfer can now be applied in semiconductor production. This is how Levitech meets market requirements and increases throughput speed at the same time.