Methods and systems for liquid particle prequalification

Patent metadata

Field	Value
Publication number	US-2018078975-A1
Application number	US-201615269324-A
Country	US
Kind code	A1
Filing date	Sep 19, 2016
Priority date	Sep 19, 2016
Publication date	Mar 22, 2018
Grant date	—

Abstract

Systems for prequalifying components for a processing chamber are described. The systems may be used to clean particulates from chamber parts and concurrently quantify the cleanliness. The systems may be used to qualify replacement parts before sending to a customer site for installation. The systems have three adjacent compartments separated by impermeable barriers. All three compartments are filled with liquid while cleaning a chamber component. The center compartment contains a submerged component for cleaning and qualifying. Two compartments on either side of the center compartment are configured with submerged ultrasonic transducers to deliver ultrasonic energy to either side of the component being cleaned and prequalified. A liquid pump is connected to the cleaning tub to recirculate water from the cleaning bath and another liquid pump is configured to remove a small amount of the cleaning bath to sample particulates.

First claim

1 . An ultrasonic cleaning and sampling system, comprising:
a cleaning tub; a first ultrasonic tub and a second ultrasonic tub, wherein the first ultrasonic tub is disposed on the opposite side of the cleaning tub from the second ultrasonic tub; a first impermeable barrier disposed between the first ultrasonic tub and the cleaning tub, wherein the first impermeable barrier is configured to pass ultrasonic energy from the first ultrasonic tub into the cleaning tub when each of the first ultrasonic tub and the cleaning tub are filled with water; a second impermeable barrier disposed between the second ultrasonic tub and the cleaning tub, wherein the second impermeable barrier is configured to pass ultrasonic energy from the second ultrasonic tub into the cleaning tub when each of the second ultrasonic tub and the cleaning tub are filled with water; a first ultrasonic transducer and a second ultrasonic transducer, wherein the first ultrasonic transducer is in the first ultrasonic bath and the second ultrasonic transducer is in the second ultrasonic bath; an ultrapure water source configured to deliver ultrapure water into the cleaning bath; a sampling pump fluidly coupled to the cleaning bath and configured to remove contaminated water from the cleaning bath; a liquid particle counter fluidly coupled to the dilution unit and configured to measure the particle concentration of the contaminated water using optical scattering; a recirculation pump fluidly coupled to the cleaning bath; a large particle filter fluidly coupled to the recirculation pump; and a small particle filter fluidly coupled to the large particle filter, wherein a recirculation path connects to the cleaning bath at an outlet and an inlet and the recirculation path comprises the recirculation pump, the large particle filter and the small particle filter.

2 . The ultrasonic cleaning and sampling system of claim 1 wherein the first ultrasonic transducer is configured to be driven at a first frequency which is greater than 20 kHz to produce cavitation in the cleaning tub.

3 . The ultrasonic cleaning and sampling system of claim 1 wherein the first ultrasonic transducer and the second ultrasonic transducer are configured to be driven at a same frequency to concurrently produce cavitation in the cleaning tub.

4 . The ultrasonic cleaning and sampling system of claim 1 wherein the first ultrasonic transducer is configured to be driven at a first megasonic frequency to produce cavitation in the cleaning tub.

5 . The ultrasonic cleaning and sampling system of claim 1 wherein a recirculation pumping speed of the recirculation pump is between 10 liters/min and 200 liters/min.

6 . The ultrasonic cleaning and sampling system of claim 1 wherein the first ultrasonic tub is configured such that the first ultrasonic transducer is submersible.

7 . The ultrasonic cleaning and sampling system of claim 1 wherein the small particle filter is selected to remove particles larger than 10 nm while passing particles smaller than 10 nm.

8 . The ultrasonic cleaning and sampling system of claim 1 wherein the large particle filter is selected to remove particles larger than 30 nm while passing particles smaller than 30 nm.

9 . The ultrasonic cleaning and sampling system of claim 1 wherein the recirculation path further comprises an ion-exchange filter.

10 . An ultrasonic cleaning and sampling system, comprising:
a cleaning tub; a first ultrasonic tub and a second ultrasonic tub, wherein the first ultrasonic tub is disposed on the opposite side of the cleaning tub from the second ultrasonic tub; a first impermeable barrier disposed between the first ultrasonic tub and the cleaning tub, wherein the first impermeable barrier is configured to pass ultrasonic energy from the first ultrasonic tub into the cleaning tub when each of the first ultrasonic tub and the cleaning tub are filled with water; a second impermeable barrier disposed between the second ultrasonic tub and the cleaning tub, wherein the second impermeable barrier is configured to pass ultrasonic energy from the second ultrasonic tub into the cleaning tub when each of the second ultrasonic tub and the cleaning tub are filled with water; a first ultrasonic transducer and a second ultrasonic transducer, wherein the first ultrasonic transducer is in the first ultrasonic bath and the second ultrasonic transducer is in the second ultrasonic bath; an ultrapure water source configured to deliver ultrapure water into the cleaning bath; a sampling pump fluidly coupled to the cleaning bath and configured to remove contaminated water from the cleaning bath; a dilution unit fluidly coupled to the sampling pump and configured to dilute the contaminated water by a factor of at least 500; and a liquid particle counter fluidly coupled to the dilution unit and configured to measure the particle concentration of the contaminated water using optical scattering.

11 . The ultrasonic cleaning and sampling system of claim 10 wherein a sampling pumping speed of the sampling pump is between 0.001 milliliters/min and 10 milliliters/min.

12 . The ultrasonic cleaning and sampling system of claim 10 wherein the dilution unit is configured to dilute the contaminated water by a factor of at least 500 by adding at least 500 times more ultrapure water from the ultrapure water source.

13 . The ultrasonic cleaning and sampling system of claim 10 wherein each of the first impermeable barrier and the second impermeable barrier are sheets of polypropylene, plastic, glass or quartz.

14 . The ultrasonic cleaning and sampling system of claim 10 wherein the liquid particle counter is configured to detect particle sizes down to and including 100 nm.

15 . A method of removing a contaminant from a surface of a part to-be-cleaned, the method comprising:
placing the part to-be-cleaned into a cleaning tub disposed between a first ultrasonic tub and a second ultrasonic tub; filling the cleaning tub with ultrapure water to form a cleaning bath; filling the first ultrasonic tub and the second ultrasonic tub with water; applying ultrasonic energy at a first frequency to a first ultrasonic transducer and at a second frequency to a second ultrasonic transducer, wherein the first ultrasonic transducer is disposed within the first ultrasonic tub and the second ultrasonic transducer is disposed within the second ultrasonic tub; transmitting the ultrasonic energy through the water across an impermeable barrier and into the cleaning bath; removing the contaminant from the surface; forming contaminated water by adding the contaminant to the cleaning bath; flowing the contaminated water into a liquid particle counter; and determining a contamination concentration of the contaminated water in the liquid particle counter.

16 . The method of removing a contaminant from a surface of a part to-be-cleaned of claim 15 wherein the contamination concentration is compared to an endpoint contamination concentration and the ultrasonic energy is stopped if the contamination concentration is less than the endpoint contamination concentration.

Assignees

• Applied Materials Inc

Inventors

• Bhoyar Sankesha
• Arcot Mahesh
• Bagul Nilesh Chimanrao
• Raju Hemantha
• Patil Ravindra

Classifications

• B08B3/12 Primary

  by sonic or ultrasonic vibrations · CPC title

• B08B3/14

  Removing waste, e.g. labels, from cleaning liquid · CPC title

• G01N2015/0693

  Physics · mapped topic

• C02F2103/346

  from semiconductor processing, e.g. waste water from polishing of wafers · CPC title

• G01N15/0618

  of the filter type (G01N15/0643 takes precedence) · CPC title