Apparatus and method for inspecting droplet

Patent metadata

Field	Value
Publication number	US-11577506-B2
Application number	US-202117467266-A
Country	US
Kind code	B2
Filing date	Sep 5, 2021
Priority date	Sep 8, 2020
Publication date	Feb 14, 2023
Grant date	Feb 14, 2023

Abstract

Disclosed are an apparatus and a method for quickly and accurately inspecting a droplet on a substrate. An apparatus for inspecting a droplet on a substrate according to an exemplary embodiment of the present disclosure includes: an ultrasonic sensor configured to apply an ultrasonic wave to a droplet on the substrate and detect an ultrasonic wave reflected from the substrate; and a processor configured to acquire a height of the droplet at each position on the substrate on the basis of a signal of the ultrasonic wave reflected from the droplet on the substrate, calculate a volume of the droplet on the basis of the heights of the droplet at the positions, and store or output data in relation to the volume of the droplet. The embodiment of the present disclosure may calculate the volume of the droplet using the ultrasonic wave, thereby quickly and accurately inspecting the droplet on the substrate.

First claim

What is claimed is:

1. An apparatus for inspecting a droplet on a substrate, the apparatus comprising:
an ultrasonic transmitter configured to apply an ultrasonic wave to a droplet on the substrate;
an ultrasonic receiver configured to detect an ultrasonic wave reflected from the droplet on the substrate and convert the detected ultrasonic wave to an electrical signal; and
a processor configured to acquire a plurality of heights of the droplet at a plurality of positions on the substrate on the basis of the electrical signal that is received from the ultrasonic receiver, calculate a volume of the droplet on the basis of the plurality of heights of the droplet at the plurality of positions, and store or output data in relation to the volume of the droplet.

2. The apparatus of claim 1 ,
wherein the processor creates a three-dimensional graphic image corresponding to a shape of the droplet on the basis of the plurality of heights of the droplet at the plurality of positions on the substrate, calculates a volume of the three-dimensional graphic image corresponding to the shape of the droplet, and controls an amount of liquid to be discharged toward the substrate by comparing the volume with a reference volume, and
wherein the plurality of positions are represented by two dimensional coordinates.

3. The apparatus of claim 2 ,
wherein the processor creates a three-dimensional graph representing the plurality of heights of the droplet at the plurality of positions on the substrate, and models the three-dimensional graphic image corresponding to the shape of the droplet by applying interpolation to two adjacent heights of the plurality of heights in the three-dimensional graph.

4. The apparatus of claim 2 ,
wherein the processor determines whether the shape of the droplet is within a reference shape range on the basis of the three-dimensional graphic image.

5. The apparatus of claim 1 ,
wherein the ultrasonic transmitter and the ultrasonic receiver are positioned below the substrate.

6. The apparatus of claim 5 ,
wherein the ultrasonic transmitter and the ultrasonic receiver are installed in a support unit configured to support the substrate.

7. The apparatus of claim 5 , further comprising:
an inspection operating part configured to position the ultrasonic transmitter and the ultrasonic receiver below the substrate onto which the droplet is discharged.

8. The apparatus of claim 7 ,
wherein the inspection operating part comprises:
a horizontal drive part configured to convey the substrate to an inspection zone in which the droplet is inspected; and
a vertical drive part configured to move upward the ultrasonic transmitter and the ultrasonic receiver positioned below the substrate positioned in the inspection zone so that the ultrasonic transmitter and the ultrasonic receiver contact a lower portion of the substrate.

9. The apparatus of claim 1 ,
wherein the ultrasonic transmitter and the ultrasonic receiver are positioned above the substrate.

10. The apparatus of claim 9 ,
wherein the ultrasonic transmitter and the ultrasonic receiver are installed on a head unit configured to discharge the droplet or installed on a structure positioned above the substrate.

11. A method of inspecting a droplet on a substrate, the method comprising:
applying, using an ultrasonic transmitter, an ultrasonic wave to a droplet on the substrate;
detecting, using an ultrasonic receiver, an ultrasonic wave reflected from the droplet on the substrate and converting the detected ultrasonic wave to an electrical signal;
acquiring a plurality of heights of the droplet at a plurality of positions on the substrate on the basis of the electrical signal received from the ultrasonic receiver;
calculating a volume of the droplet on the basis of the plurality of heights of the droplet at the plurality of positions; and
storing or outputting data in relation to the volume of the droplet.

12. The method of claim 11 ,
wherein the calculating of the volume of the droplet comprises:
creating a three-dimensional graphic image corresponding to a shape of the droplet on the basis of the plurality of heights of the droplet at the plurality of positions on the substrate;
calculating a volume of the three-dimensional graphic image corresponding to the shape of the droplet; and
controlling an amount of liquid to be discharged toward the substrate by comparing the volume with a reference volume, and
wherein the plurality of positions are represented by two dimensional coordinates.

13. The method of claim 12 ,
wherein the creating of the three-dimensional graphic image corresponding to the shape of the droplet comprises:
creating a three-dimensional graph representing the plurality of heights of the droplet at the plurality of positions on the substrate; and
modeling the three-dimensional graphic image corresponding to the shape of the droplet by applying interpolation to two adjacent heights of the plurality of heights in the three-dimensional graph.

14. The method of claim 12 , further comprising:
determining whether the shape of the droplet is within a reference shape range on the basis of the three-dimensional graphic image.

15. The method of claim 11 ,
wherein the applying of the ultrasonic wave to the droplet on the substrate comprises:
positioning an ultrasonic transmitter and an ultrasonic receiver below the substrate onto which the droplet is discharged; and
applying the ultrasonic wave to the droplet from the ultrasonic transmitter and the ultrasonic receiver.

16. The method of claim 15 , wherein the positioning of the ultrasonic transmitter and the ultrasonic receiver below the substrate comprises:
conveying the substrate to an inspection zone in which the droplet is inspected; and
moving upward the ultrasonic transmitter and the ultrasonic receiver positioned below the substrate positioned in the inspection zone so that the ultrasonic transmitter and the ultrasonic receiver contact a lower portion of the substrate.

17. An inkjet printing facility comprising:
a substrate loading part configured to load a substrate;
a substrate conveying part configured to convey the substrate;
a substrate processing part comprising a support unit on which the substrate is seated, a head unit configured to discharge a droplet onto the substrate seated on the support unit, and a gantry to which the head unit is movably coupled;
a facility inspection part configured to inspect a module comprised in the substrate processing part;
an apparatus for inspecting the droplet discharged by the head unit, the apparatus being comprised in the substrate processing part or the facility inspection part; and
a substrate unloading part configured to unload the substrate,
wherein the apparatus for inspecting the droplet comprises:
an ultrasonic sensor configured to apply an ultrasonic wave to the droplet from above or below the substrate, detect an ultrasonic wave reflected from the droplet on the substrate, and convert the detected ultrasonic wave to an electrical signal; and
a processor configured to acquire a plurality of heights of the droplet at a plurality of positions on the substrate on the basis of the electrical signal that is received from the ultrasonic sensor, calculate a volume of the droplet on the basis of the plurality of heights of the droplet at the plurality of positions, and output or store data in relation to the volume of the droplet.

18. The inkjet printing facility of claim 17 ,
wherein the processor creates a three-dimensional graphic image

Assignees

• Semes Co Ltd

Inventors

• Kim Kwang Sup
• Ahn Dong Ok
• Lee Jong Min
• Oh Jun Ho
• Yoo Ji Hoon
• Park Young Ho

Classifications

• G01N15/00 Primary

  Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials · CPC title

• G06T7/62 Primary

  of area, perimeter, diameter or volume · CPC title

• B41J2/1752

  Mounting within the printer · CPC title

• G01B17/02

  for measuring thickness · CPC title

• B41J29/38

  Drives, motors, controls or automatic cut-off devices for the entire printing mechanism · CPC title