Wafer cleaning system
First Claim
1. A cleaning apparatus comprising:
- a probe having a solid, elongated forward portion with a substantially constant cross section, and a rear portion with a cross-sectional area larger than the cross-sectional area of said forward portion, said probe being made of a material which efficiently transmits megasonic vibration energy;
a heat transfer member made of material which is a better heat conductor than that of the probe having one end phase coupled to an end phase of said probe rear portion;
a container for receiving a cleaning fluid and a wafer to be cleaned, said probe being supported so that said forward portion of the probe is positioned in the container while the probe rear portion is positioned outside of the container; and
a vibrator coupled to an opposite end face of said member for megasonically vibrating said probe with energy transmitted through the member to produce substantial lateral vibration along the length of the probe so as to dislodge particles on a flat surface of the wafer when said probe forward portion is positioned close to and parallel to the flat surface and the cleaning fluid is applied to the flat surface and said probe forward portion to create a miniscus of fluid between the probe and the flat surface.
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0 Petitions
Accused Products
Abstract
A wafer cleaning system cleans semiconductor wafers using megasonic energy to agitate cleaning fluid applied to the wafer. A source of acoustic energy vibrates an elongated quartz probe which transmits the acoustic energy into the fluid. One form of the probe has a solid cylindrical-shaped cleaning portion within the tank and a flared rear portion with an increasing diameter outside the tank. A heat transfer member acoustically coupled to the larger rear portion of the probe and to a transducer conducts heat away from the transducer. A housing for the heat transfer member and transducer supports those components and provides means for conducting coolant through the housing to control the temperature of the transducer. In one arrangement, fluid is sprayed onto both sides of a wafer while a probe is positioned close to an upper side. In another arrangement, a short probe is positioned with its end face close to the surface of a wafer, and the probe is moved over the wafer as it rotates. The probe may also be positioned through a central hole in a plurality of discs to clean a group of such elements at one time.
197 Citations
28 Claims
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1. A cleaning apparatus comprising:
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a probe having a solid, elongated forward portion with a substantially constant cross section, and a rear portion with a cross-sectional area larger than the cross-sectional area of said forward portion, said probe being made of a material which efficiently transmits megasonic vibration energy; a heat transfer member made of material which is a better heat conductor than that of the probe having one end phase coupled to an end phase of said probe rear portion; a container for receiving a cleaning fluid and a wafer to be cleaned, said probe being supported so that said forward portion of the probe is positioned in the container while the probe rear portion is positioned outside of the container; and a vibrator coupled to an opposite end face of said member for megasonically vibrating said probe with energy transmitted through the member to produce substantial lateral vibration along the length of the probe so as to dislodge particles on a flat surface of the wafer when said probe forward portion is positioned close to and parallel to the flat surface and the cleaning fluid is applied to the flat surface and said probe forward portion to create a miniscus of fluid between the probe and the flat surface. - View Dependent Claims (2, 3)
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4. A cleaning apparatus comprising:
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a container for receiving an article to be cleaned; a support for said article within said container; a probe having an elongated forward portion; a support for said probe that positions an elongated side of said probe forward portion in said container generally parallel to a flat surface of said article; a source of fluid for applying fluid onto the article, said probe forward portion being sufficiently close to the article so that if fluid extends between the probe and the article, particles on the surface of said article are loosened when said probe oscillates in a megasonic frequency to agitate said fluid; and a transducer coupled to said probe, said transducer being adapted to oscillate at said frequency for propagating megasonic energy through said probe and laterally into said fluid between the probe and the article. - View Dependent Claims (5, 6, 7, 8, 9, 10, 11)
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12. An apparatus for cleaning semiconductor wafers comprising:
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a tank for receiving cleaning fluid and a wafer to be cleaned; a probe including an elongated portion extending into said tank through a tank wall to be positioned adjacent the flat surface of a wafer to be cleaned, and said probe including a rear portion positioned exterior to the container; a heat transfer member acoustically coupled to the probe rear portion; a transducer acoustically coupled to a rear portion of said heat transfer member to megasonically vibrate the probe; and a housing enclosing said heat transfer member and said transducer and mounted to said tank and supporting the heat transfer member, the transducer and the probe with said probe elongated portion being supported in cantilever fashion. - View Dependent Claims (13, 14, 15)
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16. A cleaning apparatus comprising:
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a container for receiving cleaning fluid in an article to be cleaned; a probe assembly including an elongated probe portion positioned within the container to be located adjacent to and parallel to a flat surface of said article, and including a rear portion positioned outside of the container, said rear portion having a cross section on one end substantially equal in size to the section of the elongated portion within the container and having an opposite end which is larger in cross section than said one end; and a transducer coupled to said opposite end adapted to oscillate at a frequency for propagating sonic energy into said container through said probe. - View Dependent Claims (17)
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18. A cleaning apparatus comprising:
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a container for receiving cleaning fluid; a probe assembly including an elongated probe forward portion extending through and generally perpendicular to a side wall of the container, the assembly including a transducer coupled to the probe for applying megasonic energy to the probe so as to cause vibration of the probe; and one or more disk-like elements each having a central aperture larger than said probe forward portion, said elements being supported in the container in a generally spaced, parallel, vertical orientation so that when the elements are immersed in cleaning liquid and the probe extends in such apertures, megasonic energy is transmitted laterally outwardly from said probe forward portion along the surfaces of said elements to loosen particles on said elements. - View Dependent Claims (19, 20, 21, 22, 23, 28)
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24. Apparatus for cleaning a semiconductor wafer comprising:
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a support for supporting the wafer; a sprayer for spraying cleaning fluid on an upper surface of the wafer; a sprayer for spraying cleaning fluid on a lower surface of the wafer; a probe positioned adjacent the upper surface of the wafer for loosening particles on the upper and lower surfaces of the wafer when megasonic energy is applied to the probe. - View Dependent Claims (25)
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26. A cleaning apparatus for loosening and removing particles from an article having a planar surface, comprising:
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a support for said article; a probe having an elongated side surface extending close to and generally parallel to the planar surface of said article; a nozzle positioned to apply cleaning fluid between said probe side surface and said planar surface, said probe being sufficiently close to said surface so that a meniscus of said fluid is formed along the length of said probe between the probe and said surface; a transducer coupled to the probe and adapted to oscillate at a frequency for propagating megasonic energy through the probe and into said meniscus; and a motor producing relative movement between the probe and said planar surface while said meniscus is maintained.
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27. An apparatus for loosening and removing particles from a semiconductor wafer, comprising:
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a rotatable support for said wafer; an elongated probe having a forward portion having a side surface extending close to but spaced from and generally parallel to an upper planar surface of said wafer, said probe having a rear portion spaced from an outer edge of said wafer which has a cross-sectional area greater than said forward portion; a heat-transfer member coupled to said probe rear portion; a transducer coupled to a side of said heat transfer member opposite from the rear portion of said probe and adapted to propagate megasonic energy through the heat transfer member and into the probe the cross sectional area of said transducer being greater than said probe forward portion; and a nozzle positioned to apply cleaning fluid between the side surface of the forward portion of said probe and said wafer planar surface, said probe forward portion being sufficiently close to said wafer surface that a meniscus of said fluid is formed between the probe and said wafer so that particles on the surface are loosened by the vibrations toward and away from the wafer along the length of said probe produced by the said megasonic energy, and said particles are carried away by said fluid.
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Specification