Conduction cooling plate using friction welding

A target assembly for semiconductor processing, the target assembly comprising:

• a target material;
• a backing plate comprising:
• a target surface;
• and
• a cooling surface disposed opposite the target surface;
• and
• a cooling plate assembly, the cooling plate assembly disposed apart from the target material by the backing plate, the cooling plate assembly disposed in a wedge shape, the cooling plate assembly comprising:
• a first plate comprising:
• a first surface;
• an inlet disposed on a first surface of the first plate;
• an outlet disposed on the first surface of the first plate;
• and
• a first channel surface, the first channel surface disposed opposite the first surface;
• a second plate comprising:
• a second channel surface disposed opposite the second surface;
• and
• a middle plate disposed between the first plate and the second plate, the middle plate comprising a channel wall separating the first channel surface from the second channel surface, the first channel surface, the second channel surface, and the channel wall defining a flow path from the inlet to the outlet, wherein the first plate, the second plate, and the middle plate comprise copper and nickel.

A method of forming a cooling plate assembly for semiconductor manufacturing, the method comprising:

• forming a first plate, a second plate, and a middle plate into a wedge shape, wherein the first plate, the second plate, and the middle plate comprise copper;
• friction welding a first channel surface of the first plate to the middle plate;
• and
• friction welding a second channel surface of the second plate to the middle plate, the middle plate disposed between the first plate and the second plate, the friction welding forming a flow path defined by the first plate, the second plate, and the middle plate within a cooling plate assembly.