Sputtering device and target with cover to hold cooling fluid

• US 5,603,816 A
• Filed: 06/05/1995
• Issued: 02/18/1997
• Est. Priority Date: 11/24/1993
• Status: Expired due to Term

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Demaray, Richard E., Berkstresser, David E., Herrera, Manuel
• Primary Examiner(s): Weisstuch, Aaron
• Application Number:
  US08/461,822
• Time in Patent Office: 624 Days
• Field of Search: 204/298.07, 204/298.08, 204/298.09
• US Class Current: 204/298.07
• CPC Class Codes: C23C 14/3407 Cathode assembly for sputtering apparatus, e.g. Target
• CPC Class Codes: C23C 14/564 Means for minimising impurities in the coating chamber such as dust, moisture, residual gases
• CPC Class Codes: F28F 3/12 Elements constructed in the shape of a hollow panel, e.g. with channels F28D1/02, F28D1/03 take precedence
• CPC Class Codes: H01J 2237/022 Avoiding or removing foreign or contaminating particles, debris or deposits on sample or tube
• CPC Class Codes: H01J 37/32458 Vessel
• CPC Class Codes: H01J 37/3411 Constructional aspects of the reactor
• CPC Class Codes: H01J 37/3435 Target holders (includes backing plates and endblocks)
• CPC Class Codes: H01J 37/3497 Temperature of target

Abstract

A target, target backing plate, and cover plate form a target plate assembly. The sputtering target assembly includes an integral cooling passage. A series of grooves are constructed in either the target backing plate or the target backing cooling cover plate, which are then securely bonded to one another. The sputtering target can be a single monolith with a target backing plate or can be securely attached to the target backing plate by one of any number of conventional bonding methods. Tantalum to titanium, titanium to titanium and aluminum to titanium, diffusion bonding can be used.

The target plate assembly completely covers and seals against a top opening of a sputtering processing chamber. Cooling liquid connections are provided only from the perimeter of the target assembly. When a top vacuum chamber seals the side opposite the pressure chamber, the pressure on both sides of the target assembly is nearly equalized. Large thin target assemblies, such as large flat plates used for flat panel displays can be sputtered effectively and uniformly without adverse sputtering effects due to target deflection or cooling deficiencies.

The energized target assembly is protected from adjacent components by overlapping insulators to prevent accidents and isolate the target assembly from other components. An electrical connection to the target assembly remains unconnected until a vacuum is produced in the top chamber.

Claims

1. A sputtering device comprising:

a substrate processing chamber having a target assembly covering and sealing the top opening of the processing chamber;

a top vacuum chamber having a lower opening similar in size to said top opening of said processing chamber, said lower opening generally being covered and sealed with said target assembly;

processing chamber vacuum means to create a vacuum in the processing chamber;

top vacuum chamber vacuum means for creating a vacuum in said top vacuum chamber; and

an electrical connection to said target assembly, said connection including a safety device providing an open circuit, between a power source and said target assembly when a predetermined vacuum pressure is not provided to said top vacuum chamber and a closed circuit when a vacuum pressure equal to or greater than said predetermined vacuum pressure is provided.

2. The sputtering device as in claim 1,

wherein said safety device includes a set of contacts separated by a set of non-conducting elastic members, such that said safety device is configured so that said elastic members separate said contacts when said predetermined vacuum pressure is not provided and said elastic members are strained to allow said contacts to touch when a vacuum pressure equal to or greater than said predetermined vacuum pressure is provided.