Integrated megasonic cascade scrubber module and process

• US 7,516,507 B1
• Filed: 11/08/2004
• Issued: 04/14/2009
• Est. Priority Date: 11/10/2003
• Status: Expired due to Fees

• Current Assignee: Xyratex Technology Limited (Seagate Technology Holdings Plc)
• Original Assignee: Xyratex Technology Limited (Seagate Technology Holdings Plc)
• Inventors: Mehmandoust, Yassin, Petersen, Scott, Oxsen, Michael
• Primary Examiner(s): CHIN, RANDALL E
• Application Number:
  US10/984,321
• Time in Patent Office: 1,618 Days
• Field of Search: 15/211, 15/77, 151/02
• US Class Current: 15/77
• CPC Class Codes: B08B 1/32 using rotary cleaning members
• CPC Class Codes: B08B 3/12 by sonic or ultrasonic vibrations washing or rinsing machines for crockery or tableware using sonic or ultrasonic waves A47L15/13; of natural teeth, of prostheses using ultrasonic techniques similar to those used for natural teeth A61C17/20; application of ultrasonic vibrations to chemical, physical or physico-chemical processes in general B01J19/10
• CPC Class Codes: G11B 23/505 of disk carriers
• CPC Class Codes: H01L 21/67046 using mainly scrubbing means, e.g. brushes

Abstract

Substrate preparation systems comprising multi-zone cascade brush scrubbers having sonic assemblies disposed between one or more of the scrubber zones for cleaning of disk-shaped substrates, including silicon wafers and disks for data storage devices, such as hard disk drives (HDD), compact discs (CD) and digital video discs (DVD). The system method combines a sonic particle dislodgement/removal assembly into a cascade brush scrubber line comprising a longi-tudinal array of brush pairs in which the substrates process through preparation zones defined by each pair of brushes, the substrates being transited longitudinally through the zones while rotating on an axis normal to their faces. Piezoelectric transducer arrays transmit sound energy to one or both face(s) of the substrate to dislodge and/or remove particles, and the scrubber simultaneously or thereafter sweeps away the particulates. The sonic energy may be ultrasonic, megasonic, or both, applied to the substrate surface(s) in alternating or sequential process steps.

Claims

1. Apparatus system for preparation of disk-shaped substrates having opposed, generally planar faces that require cleaning in preparation for fabrication of computer chips and storage device media, comprising in operative combination:

a) a cascade scrubber assembly having a pair of rotatable, laterally spaced, longitudinally extending mandrels, the axes of which are oriented in parallel relationship, each of said mandrels having mounted thereon a plurality of spaced cylindrical brush elements to form a plurality of brush pairs from a first input end of said scrubber assembly to an output end, said brush pairs are spaced apart from each other along the respective axes of said mandrels;

said brush pair being dimensioned to provide a lateral nip therebetween for vertically supporting said substrate disk and for contacting said substrate faces, each said brush pair defining a substrate cleaning zone that is spaced from a sequentially-adjacent brush element pair, each of said brush pair spacings defining an inter-zone gap along said mandrels, a first drive mechanism to transport said substrates disks along said brush pair nips from said input end to said output end of said cascade scrubber assembly, and a second drive mechanism for rotating said substrates as they are transported from said input end to said output end of said cascade scrubber assembly;

b) at least one sonic particle dislodgement assembly disposed in at least one of said inter-zone gaps, said sonic assembly including at least one transducer and at least one transmitter member having an output surface for delivery of sound energy, selected from ultrasonic and megasonic energy, to at least one surface of a substrate in fluid-coupled association therewith;

c) a conduit for supply of fluid to at least one output surface of said sonic assembly to provide a fluid for coupling between said sonic assembly output surface and at least one face of said substrates; and

d) said apparatus providing sequential scrubbing and microscopic particle dislodgement from at least one surface of said substrates as said substrates are moved along said scrubber assembly from said input end to said output end of said cascade scrubber assembly.

2. Apparatus for preparation of substrates as in claim 1 wherein said sonic assembly comprises an array of transducers and said transmitter member output surface is disposed spaced from said disk surface to provide a meniscus coupling gap for said fluid coupling to said disk surface as said substrate disk is transported adjacent thereto.

3. Apparatus for preparation of substrates as in claim 2 wherein a sonic assembly is disposed in each said inter-zone gap of said cascade scrubber assembly.

4. Apparatus for preparation of substrates as in claim 2 wherein a sonic assembly is disposed in from about 10% to about 50% of said inter-zone gaps of said cascade scrubber assembly, said gaps being selected from alternate gaps and gaps disposed in the downstream portion of said cascade scrubber assembly.

5. Apparatus for preparation of substrates as in claim 2 wherein said transmitter member extends from the outer edge of said substrate to at least about the center of said substrate.

6. Apparatus for preparation of substrates as in claim 2 wherein said fluid is selected from DI water and water supplemented with a washing or rinsing agent.

7. Apparatus for preparation of substrates as in claim 1 wherein a plurality of sonic assemblies are disposed adjacent the path of said substrates as they traverse the scrubber nips from said input end to said output end and at least one of said sonic assemblies is in fluid coupling with one face of said substrate and at least one other sonic assembly is in fluid coupling with the opposite face of said substrate.

8. Apparatus for preparation of substrates as in claim 1 wherein a plurality of sonic assemblies are disposed adjacent the path of said substrates as they traverse the scrubber nips from said input end to said output end, and at least one of said sonic assemblies is in fluid coupling with both faces of said substrates to deliver sonic energy to said both faces simultaneously.

9. Apparatus for preparation of substrates as in claim 1 wherein said sonic assembly includes a pair of transmitter members disposed with a space between said members, said space defining a slot including opposed faces of said transmitter members spaced apart a distance sufficient to permit passage of a substrate disk therebetween, and to provide a fluid coupling meniscus gap between each transmitter member face and a substrate face.

10. Apparatus for preparation of substrates as in claim 9 wherein each said transmitter member includes a plurality of transducers in an array to provide full coverage of said substrate face along a radius thereof.

11. Apparatus for preparation of substrates as in claim 1 wherein said sonic assembly includes fluid conduits for providing cooling fluid heat exchange internal of said assembly.

12. A continuous cascade scrubber having a plurality of spaced scrubber zones, comprising in operative combination:

a) a plurality of pairs of adjacent counter-rotating brushes, defining brush pairs;

b) said brushes being mounted along a pair of rotatable, laterally spaced, longitudinally extending mandrels, the axes of said mandrels being oriented in parallel relationship;

c) said brush pairs being spaced apart by a plurality of gaps spaced longitudinally along said mandrels, the brush pair between successive gaps defining a scrubber zone, and adjacent scrubber zones being spaced apart by a gap; and

d) at least one sonic energy-delivering assembly disposed in at least one said gap.