grinding

“Semiconductor grinding requires ultra-high stiffness, accurate rotation with minimal vibration to achieve the required wafer attributes of minimal TTV (Total Thickness Variation) and sub-surface damage. ABD has experience in designing both precision grinding and chuck, air-bearing spindles.”

Semiconductor grinding (particularly backgrinding) refers to the process of thinning silicon wafers, which is essential for the production of integrated circuits (ICs) and other electronic components. This process is crucial for achieving the desired thickness of wafers, which can significantly impact the performance and reliability of semiconductor devices.

Purpose: Wafer backgrinding is performed to reduce the thickness of silicon wafers, typically from around 750 μm to as thin as 50-25 μm. This reduction is necessary for high-density packaging of ICs, allowing for smaller and more efficient electronic devices.

Process: The backgrinding process involves removing material from the backside of the wafer. This is achieved using grinding machines equipped with specialist grinding wheels. The process is carefully controlled to minimize damage to the wafer and ensure a smooth surface finish.

“ABD grinding spindles are equipped with both direct drive brushless DC and AC motors, with Hall Effect commutation available as required, thus providing low cogging and excellent speed stability.

High stiffness (both axial and radial) is important and achieved along with minimal synchronous axial weave.

Through-shaft vacuum for chuck spindles and coolant for grinding spindles can be incorporated.”

Air bearings are used in semiconductor grinding because they offer many benefits over traditional rolling-contact bearing systems and ABD uses proprietary modelling techniques and advanced manufacturing methods to achieve high performance aerostatic grinding spindles :-