Method and system for clamping semiconductor wafers

Claim 3

A system as in claim 1, further including a raised pedestal region on the holding surface, wherein the raised annular barrier circumscribes the raised pedestal region.

Claim 4

A system as in claim 1, wherein an outer peripheral rim of the raised annular barrier includes a chamfered periphery and wherein the first surface on the ring clamp is similarly chamfered to mate and align with the barrier as the ring clamp and holding surface are brought together.

Claim 5

A system as in claim 1, wherein the raised annular barrier defines a circular cavity and the second surface on the ring clamp is shaped to conform to the irregular periphery of the semiconductor wafer; wherein the means for reciprocating the ring clamp relative to the holding surface includes a housing, means for reciprocating the housing relative to the holding surface, and means for resiliently attaching the ring clamp to the housing; wherein the holding surface is an electrode and means for reciprocating the ring clamp relative to the holding surface includes a second electrode mounted on the housing; wherein the means for resiliently attaching the ring clamp to the housing includes a plurality of spring assemblies secured about the outer periphery of the ring clamp; and wherein the individual spring assemblies comprise a lubricous cylinder, a plunger element reciprocatably mounted in the cylinder, and a spring element extending between the housing and the plunger element.

Claim 6

A semiconductcr reactor apparatus comprising: a primary housing; a first electrode mounted on the primary housing, which electrode is capable of supporting a semiconductor wafer on an exposed surface thereof; a secondary housing; a second electrode mounted on the secondary housing and having an exposed surface generally parallel to that of the first electrode; means for reciprocatably attaching the primary and secondary housings so that the exposed surfaces of the first and second electrodes are generally opposed and the distance between said electrodes is adjustable; a ring clamp; and means for resiliently mounting the ring clamp on the secondary housing so that the clamp will press against the periphery of a semiconductor wafer mounted on the first electrode as the primary and secondary housings are brought together.

Claim 7

A semiconductcr reactor apparatus comprising: a primary housing; a first electrode mounted on the primary housing, which electrode is capable of supporting a semiconductor wafer on an exposed surface thereof; a secondary housing; a second electrode mounted on the secondary housing and having an exposed surface generally parallel to that of the first electrode; means for reciprocatably attaching the primary and secondary housings so that the exposed surfaces of the first and second electrodes are generally opposed and the distance between said electrodes is adjustable; a ring clamp; and means for resiliently mounting the ring clamp on the secondary housing so that the clamp will press against the periphery of a semiconductor wafer mounted on the first electrode as the primary and secondary housings are brought together.

Claim 8

A semiconductor reactor apparatus as in claim 5, wherein the primary housing includes a cylindrical body and the secondary housing includes a cylindrical body mounted to coaxially reciprocate within the cylindrical body of the primary housing.

Claim 9

A semiconductor reactor apparatus as in claim 5, wherein the ring clamp has an opening which defines a peripheral overhang, which engages the outer periphery of the semiconductor wafer as the housings are brought together; wherein the opening has a geometry corresponding to the periphery of a semiconductor wafer having one or more edge flats; wherein the peripheral overhang defined by the opening in the ring clamp extends over the corresponding wafer by a distance no greater than about 0.15 cm in the radial direction at any location on the wafer periphery; wherein the means for resiliently mounting the ring clamp on the secondary housing includes a plurality of spring assemblies secured about the outer periphery of the ring clamp; wherein the individual spring assemblies comprise a lubricous cylinder, a plunger element reciprocatably mounted in the cylinder, and a spring element extending between the secondary housing and the plunger element; wherein the exposed region of the first electrode includes a raised pedestal region for supporting the semiconductor wafer; further comprising a raised annular barrier circumscribing the raised pedestal region to define a cavity for receiving the semiconductor wafer; and wherein the ring clamp and the annular barrier each include surfaces capable of mating when the clamp is moved toward the secondary housing, whereby the ring clamp and second electrode are properly aligned.

Claim 10

An improved method for processing semiconductor wafers having edge flats identifying crystalline orientation, said method being of the type wherein the wafer is clamped to an electrode surface using a ring clamp which overhangs the periphery of the wafer, said improvement comprising: clamping the wafer against the electrode surface with a ring clamp having a peripheral geometry which corresponds to that of the wafer, whereby the portion of the wafer covered by the clamp is minimized.

Claim 11

An improved method for processing semiconductor wafers having edge flats identifying crystalline orientation, said method being of the type wherein the wafer is clamped to an electrode surface using a ring clamp which overhangs the periphery of the wafer, said improvement comprising: clamping the wafer against the electrode surface with a ring clamp having a peripheral geometry which corresponds to that of the wafer, whereby the portion of the wafer covered by the clamp is minimized.

Claim 12

An improved method as in claim 8, wherein prior to clamping the wafer is rotationally oriented so that the edge flat location is aligned with the geometry of the ring clamp.

Claim 13

An improved method as in claim 8, wherein the ring clamp extends over the wafer by a distance no greater than about 0.15 cm in the radial direction at any location on the wafer periphery.