Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
183 words
A method for polishing a semiconductor wafer comprising the steps of mounting a first face (22) of the wafer (12) on a polishing block (14), attaching the polishing block to a wafer polisher (16) such that a second face (24) of the wafer is exposed to a polishing pad (19) of the wafer polisher for polishing the second face of the wafer, polishing the exposed second face of the wafer using the polishing pad of the wafer polisher, the method being characterized in that the polishing block and wafer are transferred as a unit after polishing to a cleaning and drying station (10), the polishing block and wafer unit are oriented in the cleaning and drying station so that the second face is accessible for cleaning, cleaning liquid is delivered to the exposed second face of the wafer for a first selected time to clean the second face of the wafer, the polishing block and wafer unit is rotated for a second time and at a rate selected to throw liquid off of the second face of the wafer for drying the wafer.
Claim 2
Dependent Claim
36 words
A method as set forth in claim 1 further characterized in that the polishing block and wafer unit (15) is rotated as the cleaning liquid is delivered to the second face (24) of the wafer (12).
Claim 3
Dependent Claim
41 words
A method as set forth in claim 2 characterized in that the wafer (12) is rotated during delivery of cleaning fluid to the second face (24) of the wafer at a rate slower than the rate selected for drying the wafer.
Claim 4
Dependent Claim
25 words
A method as set forth in claim 1 characterized in that the first and second rotation rates are controlled by a pre-programmed electronic control circuit.
Claim 5
Dependent Claim
33 words
A method as set forth in claim 1 characterized in that selected rate of rotation of the unit (15) during delivery of the cleaning liquid is between 100 and 300 revolutions per minute.
Claim 6
Dependent Claim
32 words
A method as set forth in claim 5 characterized in that the selected rate of rotation of the unit (15) during delivery of the cleaning liquid is about 200 revolutions per minute.
Claim 7
Dependent Claim
32 words
A method as set forth in claim 1 characterized in that the selected rate of rotation of the unit (15) for drying the wafer is between 900 and 1200 revolutions per minute.
Claim 8
Dependent Claim
26 words
A method as set forth in claim 7 characterized in that rotation of the unit (15) at a second rate is about 1000 revolutions per minute.
Claim 9
Dependent Claim
21 words
A method as set forth in claim 1 characterized in that the selected second time is between 60 and 90 seconds.
Claim 10
Dependent Claim
290 words
Apparatus for cleaning and drying a semiconductor wafer (12) having a first face (22) mounted on a polishing block (14) such that the wafer and polishing block form a unit (15), and a second exposed face (24) following polishing of the second face of the wafer on a wafer polisher, the apparatus (10) comprising a housing (26), a chuck (28) for mounting the polishing block and the wafer unit, a spindle (30) connected to the chuck and supported in the housing for rotating the chuck about the longitudinal axis of the spindle, means for driving rotation of the spindle, a liquid delivery line (34) disposed for selectively delivering cleaning fluid to the polishing block and wafer unit in the chuck, the apparatus being characterized in that the chuck is capable of gripping the polishing block with the second face of the wafer facing generally upward to hold the polishing block and wafer unit for rotation with the chuck, the housing comprises a base (36) having an open top through which the polishing block and wafer unit passes for mounting on the chuck and a lid (40) pivotally mounted on the base and capable of swinging motion between a closed position in which the lid closes the open top of the base to retain liquid delivered to the wafer inside the housing and an open position in which the lid is swung away to expose the open top of the base, the liquid delivery line being mounted on the lid for motion therewith such that the line is disposed generally over the center of the chuck in the closed position of the lid, and further characterized in that the apparatus includes actuating means (138) for automatically opening and closing the lid.