Cathode assembly, physical vapor deposition system, and method for physical vapor deposition

Patent metadata

Field	Value
Publication number	US-2016013032-A1
Application number	US-201414327462-A
Country	US
Kind code	A1
Filing date	Jul 9, 2014
Priority date	Jul 9, 2014
Publication date	Jan 14, 2016
Grant date	—

Abstract

A cathode assembly for a physical vapor deposition (PVD) system includes a target holder and a thickness detector. The target holder is for holding a target, in which the target has a first major surface and a second major surface. The first major surface and the second major surface are respectively proximal and distal to the target holder. The thickness detector is disposed on the target holder. At least one portion of the first major surface is exposed to the thickness detector for allowing the thickness detector to detect the thickness of the target through the first major surface.

First claim

What is claimed is:

1 . A cathode assembly for a physical vapor deposition (PVD) system, the cathode assembly comprising:
a target holder for holding a target, wherein the target has a first major surface and a second major surface, and the first major surface and the second major surface are respectively proximal and distal to the target holder; and a thickness detector disposed on the target holder, wherein at least one portion of the first major surface is exposed to the thickness detector for allowing the thickness detector to detect the thickness of the target through the first major surface.

2 . The cathode assembly of claim 1 , wherein the thickness detector comprises:
a wave generator configured for applying a wave to the target through the first major surface of the target; a wave receiver configured for receiving the wave reflected by the second major surface of the target; and a computing unit configured for determining the thickness of the target according to a time difference between the applying of the wave and the receiving of the wave and the velocity of the wave in the target.

3 . The cathode assembly of claim 1 , wherein the thickness detector comprises:
a wave generator configured for applying an ultrasonic wave to the target through the first major surface of the target; a wave receiver configured for receiving the ultrasonic wave reflected by the second major surface of the target; and a computing unit configured for determining the thickness of the target according to a time difference between the applying of the ultrasonic wave and the receiving of the ultrasonic wave and the velocity of the ultrasonic wave in the target.

4 . The cathode assembly of claim 1 , wherein the thickness detector comprises:
a wave generator configured for applying an electromagnetic wave to the target through the first major surface of the target; a wave receiver configured for receiving the electromagnetic wave reflected by the second major surface of the target; and a computing unit configured for determining the thickness of the target according to a time difference between the applying of the electromagnetic wave and the receiving of the electromagnetic wave and the velocity of the electromagnetic wave in the target.

5 . The cathode assembly of claim 1 , wherein the thickness detector comprises:
a thermometer configured for measuring the temperature of the target at the first major surface; and a computing unit configured for determining the thickness of the target according to the measured temperature of the target.

6 . The cathode assembly of claim 5 , wherein the thermometer is an infrared thermometer.

7 . The cathode assembly of claim 1 , further comprising:
a magnet, wherein the target holder is disposed between the magnet and the target, the magnet has north and south poles, and a vertical projection of the thickness detector on the magnet overlaps with at least one of the north and south poles; and a rotating mechanism configured for rotating the magnet.

8 . A PVD system, comprising:
a processing chamber; a target holder disposed in the processing chamber for holding a target; a power supply in electrical communication with the target for applying a voltage to the target; a thickness detector disposed in the processing chamber for detecting a thickness of the target; a gas system configured for introducing carrier gas into the processing chamber; and a supporting member disposed in the processing chamber for holding a substrate.

9 . The PVD system of claim 8 , wherein the thickness detector comprises:
a wave generator configured for applying a wave to the target; a wave receiver configured for receiving the wave reflected by an interface between the target and an environment inside the processing chamber; and a computing unit configured for determining the thickness of the target according to the received wave.

10 . The PVD system of claim 8 , wherein the thickness detector comprises:
a wave generator configured for applying an ultrasonic wave to the target; a wave receiver configured for receiving the ultrasonic wave reflected by an interface between the target and an environment inside the processing chamber; and a computing unit configured for determining the thickness of the target according to the received ultrasonic wave.

11 . The PVD system of claim 8 , wherein the thickness detector comprises:
a wave generator configured for applying an electromagnetic wave to the target; a wave receiver configured for receiving the electromagnetic wave reflected by an interface between the target and an environment inside the processing chamber; and a computing unit configured for determining the thickness of the target according to the received electromagnetic wave.

12 . The PVD system of claim 8 , wherein the thickness detector comprises:
a thermometer configured for measuring the temperature of the target; and a computing unit configured for determining the thickness of the target according to the measured temperature of the target.

13 . The PVD system of claim 12 , wherein the thermometer is an infrared thermometer.

14 . The PVD system of claim 8 , further comprising:
a magnet, wherein the target holder is disposed between the magnet and the target, the magnet has north and south poles, and a vertical projection of the thickness detector on the magnet overlaps with one of the north and south poles; and a rotating mechanism configured for rotating the magnet.

15 . A PVD method, comprising:
providing a target in a vacuum environment; placing a substrate on a supporting member facing the target in the vacuum environment; introducing carrier gas into the vacuum environment; applying a voltage to the target; detecting a thickness of the target; and replacing the target when the thickness of the target is less than a predetermined thickness.

16 . The PVD method of claim 15 , wherein the detecting is performed when applying the voltage to the target.

17 . The PVD method of claim 15 , wherein the detecting comprises:
applying a wave to the target; receiving the wave reflected by an interface between the target and the vacuum environment; and determining the thickness of the target according to a time difference between the applying of the wave and the receiving of the wave and the velocity of the wave in the target.

18 . The PVD method of claim 15 , wherein the detecting comprises:
applying an ultrasonic wave to the target; receiving the ultrasonic wave reflected by an interface between the target and the vacuum environment; and determining the thickness of the target according to a time difference between the applying of the ultrasonic wave and the receiving of the ultrasonic wave and the velocity of the ultrasonic wave in the target.

19 . The PVD method of claim 15 , wherein the detecting comprises:
applying an electromagnetic wave to the target; receiving the electromagnetic wave reflected by an interface between the target and the vacuum environment; and determining the thickness of the target according to a time difference between the applying of the electromagnetic wave and the receiving of the electromagnetic wave and the velocity of the electromagnetic wave in the target.

20 . The PVD method of claim 15 , wherein the detecting comprises:
measuring the temperature of the target; and determining the thickness of the target according to the temperature of the target.

Assignees

• Taiwan Semiconductor Mfg Co Ltd

Inventors

• Wang Yi-Chieh
• Wang Cheng-Kuo
• Lin Chung-Han

Classifications

• H01J2237/332

  Coating · CPC title

• H01J37/347 Primary

  Thickness uniformity of coated layers or desired profile of target erosion · CPC title

• C23C14/34

  Sputtering · CPC title

• H01J37/3479

  Detecting exhaustion of target material · CPC title

• H01J37/3497

  Temperature of target · CPC title