Apparatus and method for aligning devices on carriers
An apparatus and method are provided for aligning a plurality of semiconductor devices placed on a carrier. Alignment guides are located adjacent to each device in use, and arranged such that they correspond to a desired alignment of each semiconductor device. For alignment, the semiconductor devices are held by a positioning device comprising a plurality of holders, each holder being configured to generate a force to hold a semiconductor device. Actuators are also provided that are operative to move the positioning device and holders to bias the semiconductor devices against the alignment guides to orientate the semiconductor devices until they are aligned with said alignment guides.
1. Apparatus for individually aligning a plurality of semiconductor devices in a desired orientation within respective separate pockets on a carrier, each of the pockets being sized relative to the semiconductor devices to allow freedom of movement of the semiconductor devices therein, the apparatus comprising:
separate alignment guides associated with each pocket and arranged to define the desired orientation;
a positioning device comprising a plurality of holders, each holder being configured to generate a force to hold an individual semiconductor device within its respective pocket; and
actuators operative to move the positioning device and holders to bias the individual semiconductor devices within their respective pockets against the alignment guides to the desired orientation.
2. Apparatus as claimed in claim 1 , wherein the plurality of semiconductor devices is arranged substantially on a plane, and the actuators are operative to move the positioning device and holders along a plane that is substantially parallel to the plane on which the semiconductor devices are arranged.
3. Apparatus as claimed in claim 1 , including openings formed in the carrier for the holders to extend through the carrier to hold the semiconductor devices.
4. Apparatus as claimed in claim 1 , wherein the holders are operative to hold the semiconductor devices by vacuum suction force.
5. Apparatus as claimed in claim 4 , wherein the holders comprise resilient holding surfaces.
6. Apparatus as claimed in claim 5 , wherein the resilient holding surfaces are made of anti-static rubber material.
7. Apparatus as claimed in claim 4 , wherein the holders comprise rigid holding surfaces with central cavities.
8. Apparatus as claimed in claim 7 , wherein the rigid holding surfaces are made of metal and each rigid holding surface has a hardened top surface.
9. Apparatus as claimed in claim 7 , wherein the rigid holding surfaces have top surfaces that are coplanar.
10. Apparatus as claimed in claim 1 , wherein the alignment guides comprise at least two reference edges formed on the carrier for aligning a semiconductor device in at least two directions.
11. Apparatus as claimed in claim 1 , including, a clamping plate positionable onto the carrier and operative to apply a leveling force to flatten the carrier.
12. Apparatus as claimed in claim 11 , wherein the clamping plate comprises openings corresponding to positions of the respective pockets on the carrier, whereby the semiconductor devices are accessible through the clamping plate after engagement of the clamping plate to the carrier.
13. Apparatus as claimed in claim 11 , including flexible stoppers coupled to the clamping plate for engaging the carrier and applying the leveling force.
14. Apparatus as claimed in claim 11 , wherein the alignment guides comprise at least two guiding edges mounted on the clamping plate for aligning a semiconductor device in at least two directions.
15. Apparatus as claimed in claim 1 , including grippers coupled to the carrier that are operative to contact and apply a force on at least one side of a semiconductor device towards at least one of the alignment guides and movable away from the semiconductor device to release it.
16. Apparatus as claimed in claim 1 , including rigid pins coupled to the positioning device for supporting the carrier when the holders are holding the semiconductor devices.