Kinematic coupling with textured contact surfaces
View Patent ↗A substrate kinematic coupling or guide plate for a substrate carrier having textured or patterned surfaces at the points of contact to reduce frictional forces generated between automated processing equipment and the kinematic coupling. The textured surface reduces the contact area between the processing equipment and the contact portion of the kinematic coupling, thereby reducing the resultant frictional force. By reducing the frictional force, the substrate carrier more readily settles on the mounting pins of the processing equipment, thus avoiding intolerable height and angular deviations during automated access to the substrates. Textures include, but are not limited to, a knurl pattern, ridges running laterally along the contact portions, and ridges running longitudinally along the contact portions. The textures may be formed by a blow molding, injection molding or in an overmolding process, or by a machining or imprinting process.
1. A substrate carrier comprising a container portion with bottom side and a kinematic coupling plate attached to said bottom side, the kinematic coupling plate comprising:
a base with three pairs of inclined contact surfaces defining three recesses for contacting three kinematic coupling pins, at least one of said contact surfaces having a three-dimensional pattern formed thereon to eliminate sticking with one of said kinematic coupling pins.
2. The substrate carrier of claim 1 wherein each pair of inclined surfaces has an aperture therebetween and wherein the container portion has three pairs of ribs extending therefrom exposed through the apertures for seating on the three kinematic coupling pins.
3. A substrate container for holding substrates for use in processing semiconductors, the substrate container comprising a carrier portion having a bottom side with three female kinematic coupling engagement portions thereon for engaging three male kinematic coupling projections, each of said three female kinematic coupling engagement portions having an exposed contact surface for engaging one of the three male kinematic coupling projections, each of said exposed surfaces having a three-dimensional profile formed thereon.
4. The substrate container of claim 3 wherein the three-dimensional profile of each of the exposed contact surfaces has a surface roughness of greater than 3 μm.
5. The substrate container of claim 3 , wherein the container portion comprises a shell with a bottom side and an exposed kinematic coupling plate attached to the shell at the bottom side, and wherein each of said exposed contact surfaces are part of the exposed kinematic coupling plate.
6. The substrate container of claim 3 , wherein said three-dimensional profile comprises a knurled pattern having a peak-to-valley depth of greater than 3 μm.
7. The substrate container of claim 3 wherein said three-dimensional profile comprises a series of parallel ridges having a peak-to-valley depth of greater than 3 μm.
8. The substrate container of claim 3 wherein said three-dimensional profile comprises an array of at least one of dimples and spheres having a peak-to-valley depth of greater than 3 μm.
9. The substrate container of claim 3 further comprising a door that latches to and closes said container portion.
10. A substrate carrier comprising three female kinematic coupling engagement portions, at least one of said female kinematic coupling engagement portions having a textured contact surface for engaging with a male kinematic coupling projection, said contact surface having at least a three-dimensional profile formed thereon, said profile having a peak-to-valley depth of at least 5 μm.
11. The substrate carrier of claim 10 wherein said three kinematic coupling female engagement portions are separably attached to said container portion.
12. The substrate carrier of claim 10 wherein said textured contact surface comprises a knurled pattern.
13. The substrate carrier of claim 10 wherein said each of said three female kinematic coupling engagement portions has a textured contact surface.
14. The substrate carrier of claim 10 wherein said textured contact surface comprises a series of parallel ridges.
15. The substrate carrier of claim 10 wherein said textured contact surface comprises an array of dimples or spheres.
16. The substrate carrier of claim 10 wherein said textured contact surface is on a separate piece insert molded into the substrate carrier.