Matrix Integrated Systems, Inc.

Albert Wang

Scott J Baron

Gerald M Cox

Prasad P Padmanabhan

Robert Chen

A system is disclosed for speeding workpiece thoughput in low pressure, high temperature semiconductor processing reactor. The system includes apparatus for loading a workpiece into a chamber at atmospheric pressure, bringing the chamber down to an intermediate pressure, and heating the wafer while under the intermediate pressure. The chamber is then pumped down to the operating pressure. The preferred embodiments involve single wafer plasma ashers, where a wafer is loaded onto lift pins at a position above a wafer chuck, the pressure is rapidly pumped down to about 40 Torr by rapidly opening and closing an isolation valve, and the wafer is simultaneously lowered to the heated chuck. Alternatively, the wafer can be pre-processed to remove an implanted photoresist crust at a first temperature and the chamber then backfilled to about 40 Torr for further heating to close to the chuck temperature. At 40 Torr, the heat transfer from the chuck to the wafer is relatively fast, but still slow enough to avoid thermal shock. In the interim, the pump line is further pumped down to operating pressure (about 1 Torr) behind the isolation valve. The chamber pressure is then again reduced by opening the isolation valve, and the wafer is processed.

Apparatus for increased workpiece throughput

Methods and structures are provided for extremely flat wafer chucks, allowing close thermal contact uniformly across a semiconductor processing substrate. An upper and a lower section are tightly fit to one another with flat inner surfaces in face-to-face contact. The sections also define at least one groove therebetween. The two sections have asymmetrical thickness, but the groove defined therebetween is correspondingly asymmetrical such that the groove is centered in the assembled chuck. A heater element, such as a resistive heater, is placed within the groove with some clearance prior to assembling the upper and lower sections. After assembly and tightening, the chuck is thermally cycled above the normal operating temperature prior to secondary machining, thus assuring flatness that is maintained during high temperature operation.

Method for producing flat wafer chucks

A method is disclosed for speeding workpiece thoughput in low pressure, high temperature semiconductor processing reactor. The method includes loading a workpiece into a chamber at atmospheric pressure, bringing the chamber down to an intermediate pressure, and heating the wafer while under the intermediate pressure. The chamber is then pumped down to the operating pressure. The preferred embodiments involve single wafer plasma ashers, where a wafer is loaded onto lift pins at a position above a wafer chuck, the pressure is rapidly pumped down to about 40 Torr by rapidly opening and closing an isolation valve, and the wafer is simultaneously lowered to the heated chuck. Alternatively, the wafer can be pre-processed to remove an implanted photoresist crust at a first temperature and the chamber then backfilled to about 40 Torr for further heating to close to the chuck temperature. At 40 Torr, the heat transfer from the chuck to the wafer is relatively fast, but still slow enough to avoid thermal shock. In the interim, the pump line is further pumped down to operating pressure (about 1 Torr) behind the isolation valve. The chamber pressure is then again reduced by opening the isolation valve, and the wafer is processed.

Method for increased workpiece throughput

An end-effector with integrated cooling features comprises heat transferring mechanisms that transfer heat energy away from the end-effector. The end-effector advantageously minimizes the cooling overhead of a processed substrate as it is transported from a process module to a low-cost storage cassette. The reduced cooling overhead of the processed substrate, as a consequence, improves substrate throughput. In the preferred embodiments, the heat transferring mechanisms include a high surface area heat sink connecting the substrate-supporting paddle with a robot arm. Cooling fins can enhance surface area and thus enhance heat dissipation from the heat sink. Cooling channels can extend through paddle and heat sink, either containing circulating fluid for carrying heat beyond the end-effector or a phase changing material in an enclosed heat pipe.

End-effector with integrated cooling mechanism

A workpiece support or chuck that rapidly heats and cools a semiconductor workpiece is disclosed. A heat source and a cooling source, maintained at different temperatures, alternately communicate with the chuck. In one embodiment, the heat source and cooling source alternately provide relatively &ldquo;hot&rdquo; and &ldquo;cold&rdquo; heat transfer fluids to fluid channels within the workpiece chuck. Accordingly, a semiconductor workpiece in contact with the chuck rapidly heats to the temperature of the hot fluid, or rapidly cools to the temperature of the cold fluid, depending upon which fluid flowing through the chuck. In another embodiment, the heat source comprises a movable resistive heating block at a first temperature that is placed in contact with the chuck during heating, and is removed from the chuck while colder heat transfer fluid circulates within the chuck. Optionally, inert fluid can be provided to purge heat transfer fluid from the chuck channels between heating and cooling steps.

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Moraga, CA, United States of America

Albert Wang