Cleaning and liquid contact with solids – Processes – Work handled in bulk or groups
Reexamination Certificate
1998-11-03
2001-04-17
El-Arini, Zeinab (Department: 1746)
Cleaning and liquid contact with solids
Processes
Work handled in bulk or groups
C134S002000, C134S026000, C134S030000, C134S032000, C134S037000, C134S095200, C134S902000
Reexamination Certificate
active
06216709
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates to a method and apparatus for drying a workpiece such as a substrate used in magnetic disk or integrated circuit manufacturing.
In many manufacturing processes it is necessary to treat a workpiece with a liquid and then dry the workpiece. For example, during the manufacturing of magnetic disks, one typically performs the following manufacturing steps:
1. First a nickel-phosphorus layer is plated onto an aluminum substrate;
2. The nickel-phosphorus layer is polished and textured;
3. The substrate is cleaned, rinsed and dried;
4. A series of layers are sputtered onto the substrate, e.g., an underlayer such as sputtered NiP or Cr, a magnetic cobalt alloy, and a protective hydrogenated carbon overcoat.
Immediately prior to sputtering, the substrate is cleaned and then dried. It is extremely important that when the substrate is dried, there are no impurities left on its surface.
Numerous other manufacturing processes require drying a workpiece. For example, during various semiconductor manufacturing process steps, semiconductor wafers are immersed in a liquid and then dried. It is critical that there be no impurities on the surface of these wafers after drying.
One structure for drying semiconductor wafers is discussed in European Patent Application 0 385 536 A1, incorporated herein by reference. In the '536 apparatus, a cassette of wafers is immersed in a liquid and then slowly removed from the liquid in the presence of a vapor that aids in the drying process. The cooperation of this vapor and liquid creates the so-called Marangoni effect which permits drying of the wafer without leaving “drying marks”.
During the drying process, a wafer holding mechanism is always in contact with the wafer. This leaves the possibility that there will be a contamination or drying mark at the point where the wafer is held during drying. One object of our invention is to overcome this problem.
SUMMARY
Drying apparatus in accordance with our invention comprises a container for holding a liquid and first and second structures for holding one or more workpieces. The workpiece is held by the first structure while the workpiece and the first structure are immersed in the liquid. (The second structure is also typically immersed in the liquid.) Thereafter, the liquid is slowly drained from the container until a first portion of the workpiece and a portion of the second structure are exposed and dried. Thereafter, the dry portion of the second structure is used to hold the first portion of the workpiece. The first structure is then removed from contact with the workpiece and the remainder of liquid is drained from the container. After the first structure and the remainder of the workpiece are dried, the first structure withdraws the workpiece from the container.
REFERENCES:
patent: 4722752 (1988-02-01), Steck
patent: 4778532 (1988-10-01), McConnell et al.
patent: 4911761 (1990-03-01), McConnell et al.
patent: 4917123 (1990-04-01), McConnell et al.
patent: 4984597 (1991-01-01), McConnell et al.
patent: 5421905 (1995-06-01), Ueno et al.
patent: 5569330 (1996-10-01), Schild et al.
patent: 5571337 (1996-11-01), Mohindra et al.
patent: 5884640 (1999-03-01), Fishkin et al.
patent: 5902402 (1999-05-01), Durst et al.
patent: 0 385 536 A1 (1990-09-01), None
patent: WO 96/21241 (1996-07-01), None
patent: WO 96/36068 (1996-11-01), None
Cho Jonathan Sanghun
Fung Robert Pui Chi
Musser David Paul
El-Arini Zeinab
Komag, Inc.
LandOfFree
Method for drying a substrate does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for drying a substrate, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for drying a substrate will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2457690