Wafer processing system

Claim 2

A semiconductor wafer processing machine, comprising: a first loadlock means for receiving a cassette of semiconductor wafers for processing; a second loadlock means for receiving processed wafers; at least one processing chamber; at least two wedge valves; said first loadlock means being in communication with a wafer processing chamber through a first wedge valve when said first wedge valve is open; said second loadlock means being in communication with a wafer processing chamber through a second wedge valve when said second wedge valve is open; each said loadlock means, wedge valve and processing chamber being vacuum-tight and having means for attachment to an external vacuum pumping means; computer means for controlling each said loadlock means, wedge valve and processing chamber; each said wedge valve including; a valve housing having input port and output port; a valve wedge having surfaces sealing to said input and output ports, said valve wedge sealing surfaces being sloped relative to each other, said valve wedge having a storage notch between said sealing surfaces; means for sliding said valve wedge within said housing from a sealing position to an open position so that said valve wedge is clear of a line sight through said input and output ports; a workpiece handling arm capable of being stored in a folded position in said storage notch when said valve is closed.

Claim 3

The machine of claim 1 wherein said arm includes: a proximal support piece; a proximal extensor piece; a distal support piece, said distal support piece having means for bearing the workpiece on a distal end; a distal extensor piece; and a pair of concentric shafts rotating about a first axis for delivering power and control to said arm, said proximal support piece being fixedly attached at right angles to a first of said concentric shafts, said proximal extensor piece being fixedly attached at right angles to a second of said pair of concentric shafts, said proximal extensor piece being pivotally attached to said distal extensor piece at a second axis, said proximal support piece and said distal extensor piece being pivotally attached to said distal support piece at third and fourth axes, respectively, said first, second, third and fourth axes being parallel, spacings between said axes forming a parallelogram.

Claim 4

The machine of claim 2 wherein said distal support arm is a flat blade.

Claim 5

The machine of claim 3 wherein said proximal extensor piece is much shorter than said proximal support piece.

Claim 6

The machine of claim 4 wherein said first loadlock means for receiving a cassette of semiconductor wafers includes: a vacuum chamber having a door; transmitter means for sending a closely collimated beam of radiation; receiver means for moving the cassette past the collimated beam of radiation at a constant rate of speed; signal processing means for translating interruptions in the collimated beam of radiation as a function of time into position information; computer means for receiving and storing information from said signal processing means; a small vacuum cell within the walls of the vacuum chamber, said small vacuum chamber having an opening facing the door; sealing means for sealing the door to the vacuum chamber; and means for connecting said small vacuum cell to a vacuum pumping means.

Claim 7

The machine of claim 4 wherein said transport means is an elevator which raises and lowers the cassette with the wafers in a horizontal plane.

Claim 8

The machine of claim 5 wherein said means for connecting includes a pumping isolation valve for isolating the vacuum pumping means from the small vacuum cell.

Claim 9

The machine of claim 7 wherein said means for connecting includes a venting valve for venting said small vacuum cell to atmosphere when said isolation valve is closed.

Claim 10

,9. The machine of claim 8 wherein said isolation valves and venting valves are operated electrically from a switch means mounted in a handle on the door.

Claim 11

The machine of claim 9 wherein said computer means includes means for operating the machine from a task locator system.

Claim 12

The machine of claim 1 including a chuck means for centering and clamping the wafer, said chuck means including: a platform having upper surface means for supporting the workpiece; a multiplicity of clamp means for centering and holding the workpiece on the platform, said clamp means being distributed around a perimeter of said platform, each said clamp means including a thin planar hook member and a spring member, each said thin planar hook member having an upper lip shaped to fit over the workpiece, a lower lip and a lifting slot; a lifting ring arranged around and below said upper surface means, said lifting slot of each said thin planar hook engaging said lifting ring; a spreading ring arranged around and below said upper surface means and above said lifting ring, said lower lip of each said thin planar hook engaging said spreading ring; means for moving said lifting ring; and means for moving said spreading ring.

Claim 13

The device of claim 11 including lifting pin means for receiving a workpiece from a workpiece handling mechanism and lowering said workpiece to said platform.

Claim 14

The device of claim 12 including means for temperature control of said workpiece while said workpiece is held to said platform.

Claim 15

The device of claim 13 wherein said means for temperature control includes means for passing helium gas between said upper surface means of said platform and the back of the workpiece whereby to ensure thermal contact.

Claim 16

The device of claim 14 including means for removing said platform for servicing while leaving said clamp means in place.

Claim 17

The machine of claim 15 wherein said computer means includes means for operating the machine from a task locator system.

Claim 18

An etching system for automatically processing semiconductor wafers comprising: a wafer etching chamber including vacuum pumping means, means for introduction of process gases, electrode means for sustaining a plasma, power supply means for powering said electrode means, wafer support means, wafer cooling means, and process sensing means whereby to etch said wafers; wafer handling means including a cassette chamber for receiving a cassette of wafers, means for creating a vacuum in said cassette chamber, said cassette chamber including means for automatically inventorying and measuring the position of wafers in a cassette; a wafer transfer chamber between said cassette chamber and said etching chamber for automatically moving wafers from said cassette chamber into said etching chamber and for sealing off the etching chamber from the transfer chamber during processing of a wafer in the etching chamber; said chambers being interconnected by a first wafer passageway between said cassette chamber and said transfer chamber, and a second wafer passageway between said transfer chamber and said etching chamber, and said transfer chamber containing valve means for opening and closing said passageways; wafer transport means mounted in said transfer chamber and adapted to move through said first passageway to take a wafer from a cassette in said cassette chamber and transport the wafer through the transfer chamber, through said second passageway and into said etching chamber; automatic means in said etching chamber for taking a wafer from said wafer transport means and clamping the wafer in operating position on said support means in the etching chamber; and means for moving said transport means back into said transport chamber and closing said valve means after a wafer is taken from said transport means, whereby wafers are moved individually from a cassette and into said etching chamber for etching after sealing off the etching chamber from the transport chamber.

Claim 19

An etching system for automatically processing semiconductor wafers comprising: a wafer etching chamber including vacuum pumping means, means for introduction of process gases, electrode means for sustaining a plasma, power supply means for powering said electrode means, wafer support means, wafer cooling means, and process sensing means whereby to etch said wafers; wafer handling means including a cassette chamber for receiving a cassette of wafers, means for creating a vacuum in said cassette chamber, said cassette chamber including means for automatically inventorying and measuring the position of wafers in a cassette; a wafer transfer chamber between said cassette chamber and said etching chamber for automatically moving wafers from said cassette chamber into said etching chamber and for sealing off the etching chamber from the transfer chamber during processing of a wafer in the etching chamber; said chambers being interconnected by a first wafer passageway between said cassette chamber and said transfer chamber, and a second wafer passageway between said transfer chamber and said etching chamber, and said transfer chamber containing valve means for opening and closing said passageways; wafer transport means mounted in said transfer chamber and adapted to move through said first passageway to take a wafer from a cassette in said cassette chamber and transport the wafer through the transfer chamber, through said second passageway and into said etching chamber; automatic means in said etching chamber for taking a wafer from said wafer transport means and clamping the wafer in operating position on said support means in the etching chamber; and means for moving said transport means back into said transport chamber and closing said valve means after a wafer is taken from said transport means, whereby wafers are moved individually from a cassette and into said etching chamber for etching after sealing off the etching chamber from the transport chamber.

Claim 20

An etching system as in claim 17 including a control computer having means for operating said etching system through a task locator system.

Claim 21

A processing system for processing semiconductor workpieces, said processing system comprising: a continuous chain of interconnected chambers, including an inlet cassette-receiving chamber, an outlet cassette-receiving chamber, at least one processing chamber intermediate said cassette-receiving chambers, and a transfer chamber positioned between each two of the other types of chambers in the continuous chain; each of said cassette-receiving chambers having door means for removably sealing a workpiece cassette therein, elevator means providing vertical movement to a cassette supported thereon, and means for detecting the actual vertical position of each semiconductor workpiece in a cassette positioned on said elevator means; wall means forming said chambers in a manner such that a workpiece passageway is formed between the interior of each of said transfer chambers and the interior of each of the other chambers adjacent to the respective transfer chambers; each of said transfer chambers containing valve means moveable to simultaneously open or close both of the passageways opening into the respective transfer chamber; each of said transfer chambers containing workpiece transfer means adapted to releaseably support a workpiece, means for moving said transfer means through the passageway between the respective transfer chamber and the adjacent chambers to move a workpiece from one of said adjacent chambers, through the transfer chamber, and into the other of said adjacent chambers; and said processing chamber having means therein for releaseably supporting a workpiece presented thereto by said workpiece transfer means.

Claim 22

A processing system for processing semiconductor workpieces, said processing system comprising: a continuous chain of interconnected chambers, including an inlet cassette-receiving chamber, an outlet cassette-receiving chamber, at least one processing chamber intermediate said cassette-receiving chambers, and a transfer chamber positioned between each two of the other types of chambers in the continuous chain; each of said cassette-receiving chambers having door means for removably sealing a workpiece cassette therein, elevator means providing vertical movement to a cassette supported thereon, and means for detecting the actual vertical position of each semiconductor workpiece in a cassette positioned on said elevator means; wall means forming said chambers in a manner such that a workpiece passageway is formed between the interior of each of said transfer chambers and the interior of each of the other chambers adjacent to the respective transfer chambers; each of said transfer chambers containing valve means moveable to simultaneously open or close both of the passageways opening into the respective transfer chamber; each of said transfer chambers containing workpiece transfer means adapted to releaseably support a workpiece, means for moving said transfer means through the passageway between the respective transfer chamber and the adjacent chambers to move a workpiece from one of said adjacent chambers, through the transfer chamber, and into the other of said adjacent chambers; and said processing chamber having means therein for releaseably supporting a workpiece presented thereto by said workpiece transfer means.

Claim 23

The processing system of claim 19 wherein said workpiece transfer means is an arm including: a proximal support piece; a proximal extensor piece; a distal support piece, said distal support piece having means for bearing the workpiece on a distal end; a distal extensor piece; and a pair of concentric shafts rotating about a first axis for delivering power and control to said arm, said proximal support piece being fixedly attached at right angles to a first of said concentric shafts, said proximal extensor piece being fixedly attached at right angles to a second of said pair of concentric shafts, said proximal extensor piece being pivotally attached to said distal extensor piece at a second axis, said proximal support piece and said distal extensor piece being pivotally attached to said distal support piece at third and fourth axes, respectively, said first, second, third and fourth axes being parallel, spacings between said axes forming a parallelogram.

Claim 24

The processing system of claim 19 wherein said supporting and clamping means includes: a platform having upper surface means for supporting the workpiece; a multiplicity of clamp means for centering and holding the workpiece on the platform, said clamp means being distributed around a perimeter of said platform, each said clamp means including a thin planar hook member and a spring member, each said thin planar hook member having an upper lip shaped to fit over the workpiece, a lower lip and a lifting slot; a lifting ring arranged around and below said upper surface means, said lifting slot of each said thin planar hook engaging said lifting ring; a spreading ring arranged around and below said upper surface means and above said lifting ring, said lower lip of each said thin planar hook engaging said spreading ring; means for moving said lifting ring; and means for moving said spreading ring.

Claim 25

The processing system of claim 19 wherein said valve means includes: a valve housing having input port and output port; a valve wedge having surfaces sealing to said input and output ports, said valve wedge sealing surfaces being sloped relative to each other, said valve wedge having a storage notch between said sealing surfaces; and means for sliding said valve wedge within said housing from a sealing position to an open position so that said valve wedge is clear of a line sight through said input and output ports.

Claim 26

A processing system as in claim 22 including a control computer having means for operating said processing system through a task locator system.