US 3,951,695 AGranted

Automatic end station for ion implantation system

AssigneeAccelerators, Inc.

InventorsLarry F. Templeton, Roger B. Gault

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Abstract

An Automatic End Station arrangement for use in conjunction with ion implantation apparatus to provide continuous implantation of semi-conductor wafers is disclosed. Wafers are indexed one by one out of a standard cartridge onto a conveyor track from which they are directed into the slot of a downwardly directed slotted passageway which has been defined between two appropriately sealed plate members. The wafer slides down the passageway until it is situated adjacent to a portion of the passageway in communication with an ion implantation apparatus. The wafer is stopped at that point and the passageway sealed above and below the wafer by inflating a pair of resilient tubes which extend through one of the plate members and across the opening of the passageway. An airtight chamber is thus formed from which the air may be evacuated for effective ion implantation. After the appropriate ion dosage has been directed into the wafer, the ion beam is stopped, the inflatable tubes collapsed and the wafer dropped out of the implantation chamber and indexed into another cartridge for transportation, storage or further processing. Intermediate stage evacuation chambers may be provided before and after the implantation chamber in order to prevent exposure of the implantation chamber to the atmosphere.

Claims10

Dependent claims

Automatic end station apparatus for carrying out the continuous ion implantation of semi-conductor wafers, comprising:

A body containing therein a generally slot-shaped, downwardly directed passageway;
said passageway being of a size adequate to receive a single wafer thickness and positioned in a generally downward direction so as to allow for the unobstructed passage therethrough of a wafer aided only by the force of gravity;
means for indexing wafers into said passageway in a determined time sequence;
A window in said passageway midway to the exit thereof communicating with a source of high velocity doping ions such that ions may be directed through said window at right angles to the direction of movement of wafers through said passageway;
Wafer positioning means within said passageway to stop and hold a wafer in position adjacent said window during ion implantation and to release the wafer when implantation is completed;
At least two collapsible inflatable tubes, each extending through said body and laterally across the aperture of said passageway such that when deflated the tubes do not obstruct the free passage of wafers through said passageway and when inflated they expand to close off and seal the passageway against loss of air pressure;
At least one of said tubes positioned above said window and at least one of said tubes positioned below said window such that when said tubes are fully inflated an airtight chamber is formed suitable for ion implantation of at least one wafer;
Means for individually inflating and deflating each of said tubes according to determined sequence;
Means for collecting each wafer after it has been suitably implanted and has passed out of said airtight implantation chamber and said passageway;
and
Sequence control means for controlling the indexing of wafers into and out of said passageway and into and out of said airtight implantation chamber in said passageway.

8 more elements

Apparatus for effecting the formation of a high vacuum pressure chamber suitable for the continuous ion implantation treatment of semiconductor wafers which comprises:

a body containing therein an essentially downwardly directed, generally slot-shaped passageway;
the dimensions of said passageway being suitable for the unobstructed passage therethrough of only a single wafer thickness;
an opening located in the wall of said passageway intermediate the ends of the passageway whereby communication is provided between said passageway and a source of high vacuum suitable for ion implantation;
said opening being appropriately sized to constitute a window in said passageway through which a beam of ions may be directed at right angles to the surface of a wafer suitably positioned in said passageway adjacent to said window;
and
releasable pressure sealing means for sealing and resealing that portion of the passageway immediately surrounding said window against the loss of vacuum pressure when a beam of ions is being directed through said window at the surface of a wafer positioned adjacent to said window, and for releasing said pressure when ion implantation is completed;
said releasable pressure sealing means comprising a pair of inflatable resilient tubes, each extending through said body and laterally across the aperture of said passageway, one of said tubes being positioned above said window and the other below said window;
such that when the tubes are in a deflated state they do not obstruct the passage of a wafer through said passageway, and when they are inflated said passageway is closed off and sealed to form an airtight chamber capable of maintaining vacuum pressures suitable for ion implantation.

5 more elements

Dependencies are inferred from the claim text.