Wafer cushion
Wafer cushions for use in wafer carriers include spring beams that include a first arm extending from the frame of the wafer cushion in a first direction and a second arm extending from the first arm in a second direction, and a wafer contact at the end of the second arm opposite where the second arm is joined to the first arm. The wafer cushion may contact a substrate within the wafer carrier only at the wafer contacts during normal conditions. The substrate may also contact secondary contact points on the second arm when a shock event occurs. The wafer contact can be v-groove style wafer contact. The wafer contact may include a contact surface having a convex surface where it is configured to contact the wafer.
1. A wafer cushion, comprising:
a frame; and
a plurality of spring beams, wherein each of the plurality of spring beams includes:
a first arm, joined to the frame and extending in a first direction apart from the frame to a first arm end;
a second arm joined to the first arm at the first arm end and extending in a second direction, different from the first direction, to a second arm end, and wherein the second arm is bowed toward the first arm; and
a wafer contact joined to the second arm at the second arm end, wherein the wafer contact has a width greater than a width of a portion of the second arm and the first arm, where joined to the frame, extends away from the second arm,
wherein each of the spring beams includes a secondary contact point on the second arm, located where the second arm is joined to the first arm, and wherein the secondary wafer contact is configured to contact a back of the wafer only when a shock event occurs.
2. The wafer cushion of claim 1 , wherein the plurality of spring beams is configured such that when a wafer is supported by two of the plurality of spring beams, the wafer only contacts the wafer contacts at the ends of the second arms of the two of the plurality of spring beams.
3. The wafer cushion of claim 1 , wherein the wafer contact is a V-groove wafer contact or a paddle wafer contact.
4. The wafer cushion of claim 1 , wherein the surface of the wafer contact configured to contact a wafer has a convex surface.
5. The wafer cushion of claim 1 , wherein the first arm is joined to the frame at a perimeter of the frame, and the first direction is towards a center line of the frame.
6. A wafer carrier, comprising a wafer cushion, wherein the wafer cushion includes:
a frame; and
a plurality of spring beams, wherein each of the plurality of spring beams includes:
a first arm joined to the frame and extending in a first direction apart from the frame to a first arm end;
a second arm joined to the first arm at the first arm end and extending in a second direction, different from the first direction to a second arm end, and wherein the second arm is bowed toward the first arm; and
a wafer contact joined to the second arm at the second arm end, wherein the wafer contact has a width greater than a width of a portion of the second arm and the first arm, where joined to the frame, extends away from the second arm,
wherein each of the spring beams includes a secondary contact point on the second arm, located where the second arm is joined to the first arm, and wherein the secondary wafer contact is configured to contact a back of the wafer only when a shock event occurs.
7. The wafer carrier of claim 6 , wherein the wafer cushion is mounted on a door of the wafer carrier.
8. The wafer carrier of claim 6 , wherein the wafer carrier is a front opening unified pod.
9. The wafer carrier of claim 6 , wherein the plurality of spring beams is configured such that when a wafer is supported by two of the plurality of spring beams, the wafer only contacts the wafer contacts at the ends of the second arms of the two of the plurality of spring beams when the wafer carrier is stationary.
10. The wafer carrier of claim 6 , wherein each of the wafer contacts is a V-groove wafer contact or a paddle wafer contact.
11. The wafer carrier of claim 6 , wherein the surface of the wafer contact configured to contact a wafer has a convex surface.
12. The wafer carrier of claim 6 , wherein the first arm is joined to the frame at a perimeter of the frame, and the first direction is towards a center line of the frame.