Wafers are made from monocrystalline or polycrystalline silicon ingots. These ingots are sawed into approx. 160 μm wafers using a saw wire. Afterwards the wafers are cleaned in wet chemical processes in various basins, separated and prepared for the processing to cells.
Grippers from Schmalz are used in the individual process steps to stack, buffer , fix and position the wafers with minimum cylce times and minimum breakage rates.
High output quantities
Wafer manufacturing requires cycle times of less than one second. Because of the high acceleration rates, the grippers must apply high holding and shear forces. What’s more, using the wafer gripper SWGm can integreate inspection and testing tasks during handling by using the optional integrated sensors.
Low breakage rates
The breakage rate of the process significantly affects the output quantities. For that reason, there is a high focus on handling the wafers as gently as possible. Schmalz’ wafer gripper SWGm enables minimum breakage rates compared to other handling technologies. The large contact surface and low vacuum level mean that the wafer gripper generates only minimum surface pressure, making it particularly gentle.
Contamination of the wafer surfaces must be avoided in all processes throughout the production chain. The wafer gripper SWGm with a contact surface made of contamination-free PEEK material is the optimal solution. Suction cups made oft he markless material HT1, can also be used in wafer manufacturing.
Separating the wafers
Separating the wafers places high demands on the gripping technology. The floating suction cup SBS generates a high flow rate, which is used to achieve a larger engagement distance to separate the wafers. The optional floating suction cup modules SBSm, which can be integrated into the wafer gripper SWGm, allow the advantages of the wafer gripper to be combined with the engagement distance of floating suction cups.
Handling wafers in wet bench applications
The wafer gripper SWGm wet was developed especially for handling wet wafers. The special positioning and dimensioning of the suction points allows wet wafers to be moved securely in industrial etching and cleaning processes without drying out the wafers‘ surface.