Cleaning mechanism for semiconductor singulation saws
A cleaning subsystem removes unwanted material, such as glaze, from saw blades used in a semiconductor singulation process. A cleaning module moves radially towards the saw blade and vertically with respect to the plane of the saw blade in order to enable abrasive cleaning blocks of the cleaning module to selectively remove material from either the upper and lower surfaces of the saw blade or the outer edge of the saw blade. The cleaning assembly can remove material from the saw blade at a predetermined time or position during the singulation process or upon detection of load imbalance during the rotation of the saw blade.
1. An apparatus for singularizing semiconductor devices, the apparatus comprising:
a spindle module configured to rotate a saw blade used to saw through wafers or a multi-device array during a singulation process;
a moveable, cleaning module configured to translate relative to the spindle module to achieve a position at which the cleaning module removes material from the saw blade; and
a controller configured to move the cleaning module in relation to the spindle module to perform a cleaning operation.
2. The apparatus of claim 1 , wherein the cleaning module comprises first and second cleaning blocks.
3. The apparatus of claim 2 , wherein the first cleaning block has a first surface cleaning surface and the second cleaning block has a second surface cleaning surface, wherein the first and second surface cleaning surfaces are parallel in order to clean top and bottom surfaces of the saw blade.
4. The apparatus of claim 3 , wherein the cleaning module further comprises a spring-based mechanism configured to control a distance between the two cleaning blocks.
5. The apparatus of claim 2 , wherein each cleaning block has an edge-cleaning surface in order to clean an outer edge of the saw blade.
6. The apparatus of claim 1 , further comprising:
an X-axis guide for moving the cleaning module along an X-axis in relation to the spindle module; and
a Y-axis guide for moving the cleaning module along a Y-axis in relation to the spindle module.
7. The apparatus of claim 1 , wherein the controller is configured to perform the cleaning operation after a predetermined time interval.
8. The apparatus of claim 1 , wherein the controller is configured to perform the cleaning operation after a predetermined number of cuts during the singulation process.
9. The apparatus of claim 1 , wherein the controller is configured to perform the cleaning operation after detection of a relatively high loading current.
10. A method for removing material from a saw blade of a singulation saw used to cut through wafers or a multi-device array during a singulation process, the method comprising:
rotating the saw blade on a spindle module of the singulation saw; and
moving a cleaning module of the singulation saw relative to the spindle module to remove the material from the saw blade,
wherein, in the cleaning module moving step, the cleaning module is moved to a position to remove the material from an outer edge of the saw blade.
11. The method of claim 10 , further comprising determining a home position and feed distance for the cleaning module.
12. The method of claim 11 , wherein the home position is determined through the saw blade parameter in a dicing saw program, while feed distance of the cleaning module is determined based on measurement of a radius of the saw blade.
13. The method of claim 10 , wherein, in the cleaning module moving step, the cleaning module is moved to a position to remove the material from upper and lower surfaces of the saw blade.
14. The method of claim 10 , wherein the cleaning module moving step comprises moving the cleaning module after detecting passage of a predetermined time interval.
15. The method of claim 10 , wherein the cleaning module moving step comprises moving the cleaning module after detecting occurrence of a predetermined number of cuts during the singulation process.
16. The method of claim 10 , wherein the cleaning module moving step comprises moving the cleaning module after detecting a relatively high loading current for the spindle.