Droplet visualization of inkjetting

• US 20060071957A1
• Filed: 05/04/2005
• Published: 04/06/2006
• Est. Priority Date: 10/05/2004
• Status: Abandoned Application

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Shang, Quanyuan, McPherson, Stephen F.
• Application Number:
  US11/123,502
• Publication Number:
  US 20060071957A1
• Time in Patent Office: Days
• US Class Current: 347/6
• CPC Class Codes: B41J 2/12 testing or correcting charge or deflection
• CPC Class Codes: B41J 29/393 Devices for controlling or analysing the entire machine ; Controlling or analysing mechanical parameters involving printing of test patterns

Abstract

The embodiments of the present invention describe an apparatus and a method of visualizing droplets dispensed from an inkjet printing system. A droplet visualization system is integrated with the inkjet printing system and is capable of measuring the sizes and the speeds of dispensed inkjet droplets and capturing the trajectories of the dispensed inkjet droplets. The measured information regarding the sizes, the speeds and trajectories of the droplets is feedback to the inkjet printing system to monitor and to control the dispense operation of the inkjet printing system. Due to this feedback control, the uniformities of the sizes, the speeds and the trajectories can be monitored and be improved.

Claims

1. An apparatus for visualizing inkjet droplets of an inkjet printing system, comprising:

a visualization device; and

a laser light source, wherein the laser light source is positioned to direct a laser between one or more inkjet device that can dispense inkjet droplets of the inkjet printing system and a substrate receiving surface of a substrate support of the inkjet printing system

2. The apparatus of claim 1, wherein the visualization device is a high resolution charge coupled device camera.

3. The apparatus of claim 1, wherein the laser light is a nanosecond pulsed laser.

4. The apparatus of claim 3, wherein the power of the laser light source is between about 0.001 mW to about 20 mW.

5. The apparatus of claim 1, wherein the apparatus for visualizing the inkjet droplets measure the sizes and speeds of the inkjet droplets and captures the trajectories of inkjet droplets.

26. The apparatus of claim 1, wherein the visualization device is positioned to receive light from the laser light source.

27. The apparatus of claim 1, wherein the laser light source is positioned to direct a laser at an inkjet droplet dispensed from the one or more nozzle as the inkjet droplet travels between the one or more nozzle and a substrate disposed on the substrate receiving surface.

28. The apparatus of claim 1, wherein the apparatus further comprises:

an image analyzer;

a visualization system controller which controls the visualization device and the laser light source; and

a processor, wherein the visual light source, the visualization device, the image analyzer, the visualization system controller, and the processor form a droplet visualization system, which measures the sizes and speeds of the inkjet droplets and captures the trajectories of the inkjet droplets.

29. The apparatus of claim 28, wherein the droplet visualization system determines the landing positions of the inkjet droplets upon substrates on the substrate receiving surface of the substrate support from the trajectories of inkjet droplets captured by the droplet visualization system.

30. The apparatus of claim 28, wherein the one ore more inkjet device of the inkjet printing system is controlled by a droplet controller that receives droplet information of sizes, speeds, trajectories, and landing positions from the droplet visualization system.

6. (canceled)

7. An apparatus for controlling the sizes, speeds and trajectories of dispensed inkjet droplets from an inkjet printing system, comprising:

an inkjet printing system;

a substrate support having a substrate receiving surface; and

a integrated inkjet droplet visualization module that measures the sizes and speeds of the dispensed inkjet droplets, captures the trajectories of the dispensed inkjet droplets, and sends controlling signals to the inkjet printing system based on the data of measured sizes and speeds and captured trajectories of the dispensed inkjet droplets.

8. The apparatus of claim 7, wherein the inkjet printing system comprises:

an inkjet printing module; and

an inkjet droplet controller that controls the inkjet printing module based on the information of measured sizes and speeds, and captured trajectories of the dispensed inkjet droplets;

wherein the information is collected by the integrated inkjet droplet visualization system.

9. The apparatus of claim 8, wherein the inkjet printing module comprises one or more inkjet devices that can dispense one or more color ink.

10. The apparatus of claim 7, wherein the droplet visualization module comprises:

a visualization device;

a laser light source;

a visualization system controller which controls the laser light source and the visualization device;

an image analyzer; and

a processor.

11. The apparatus of claim 10, wherein the visualization device is a high resolution charge coupled device camera.

12. The apparatus of claim 10, wherein the laser light is a nanosecond pulsed laser.

13. (canceled)

14. A method for improving uniformities of inkjet droplet sizes and speeds, comprising:

using an integrated inkjet droplet visualization module to collect information of the sizes speeds and trajectories of the dispensed inkjet droplets from an inkjet printing system; and

controlling an inkjet printing system by the collected information of the sizes, the speeds, and the trajectories of the dispensed inkjet droplets.

15. The method of claim 14, wherein the sizes, the speeds, and the trajectories of dispensed inkjet droplets are collected by using a nanosecond laser light to take double exposures of at least one of the dispensed inkjet droplets when the at least one of the dispensed inkjet droplets travels in front of a visualization device to capture at least two images of the at least one of the dispensed inkjet droplets to determine the sizes, speed, and trajectory of the at least one of the dispensed inkjet droplets.

16. The method of claim 14, wherein the dispensed droplets travels at speeds between about 2 m/s to about 12 m/s.

17. The method of claim 14, wherein the sizes of the droplets are between about 2 μ

m to about 100 μ

m in diameters.

18. The method of claim 15, wherein the time lapse between the two exposures should be between about 5 μ

s to about 2500 μ

s.

19. The method of claim 15, wherein the exposure time is less than 1000 nanoseconds.

20-25. -25. (canceled)

31. A method for visualizing inkjet droplets dispensed from an inkjet printing system comprising:

providing a first pulse of laser light source toward an inkjet droplet, dispensed from an inkjet printing system, at a first position;

recording a first image of the inkjet droplet, which is illuminated by the first pulse of laser light source, and the time of the first pulse of laser light source at the first position;

providing a second pulse of laser light source toward the inkjet droplet traveling from the first position to a second position; and

recording a second image of the inkjet droplet, which is illuminated by the second pulse of laser light source, and the time of the second pulse of the laser light at the second position.

32. The method of claim 31, further comprising:

determining the sizes of the inkjet droplet from the first and second images.

33. The method of claim 31, further comprising:

determining the speed of the of the inkjet droplet from the first and second images and from the recorded times of the first and second pulses of laser light source.

34. The method of claim 31, further comprising:

determining the trajectory of the inkjet droplet from the from the first and second images and from the recorded times of the first and second pulses of laser light source.

35. The method of claim 32, further comprising:

determining the landing position of the inkjet droplet from the from the first and second images and from the recorded times of the first and second pulses of laser light source.