Monolithic sputter target backing plate with integrated cooling passages
A single-piece backing plate for a sputtering target is disclosed where cooling passages are formed internal to the backing plate. In some embodiments, cooling passages can be formed through the edges of a single plate of material by gun drilling. These passages can then be sealed at the edge so as to form cooling passages within the plate. A sputtering target can then be bonded to one side of the plate to form a target assembly. In some embodiments, an insulating plate can be permanently bonded a side of the backing plate. Some embodiments of the target plate according to the present invention remove the need for multiple internal sealing surfaces, multiple attachment devices, and external back-side plasma suppression plates that are often utilized in conventional backing plate assemblies.
1 . A cooling backing plate for a sputter target, comprising:
a single metallic plate with a first surface for mounting a sputter target;
cooling channels formed laterally within the single metallic plate, the cooling channels being formed through the single metallic plate; and
plugs positioned in the cooling channels so as to seal and form cooling passages within the single metallic plate.
2 . The backing plate of claim 1 , wherein the cooling channels are formed through an edge of the single metallic plate.
3 . The backing plate of claim 1 , wherein the cooling channels have a diameter that is greater than ½ a thickness of the single metallic plate.
4 . The backing plate of claim 1 , wherein the single metallic plate is a material from a group consisting of titanium, aluminum, nickel, cobalt, nickel alloy, cobalt alloy, copper, and iron.
5 . The backing plate of claim 1 , wherein the single metallic plate having a lateral width greater than a substrate.
6 . The backing plate of claim 1 , wherein the single metallic plate has a smallest dimension greater than about 15 inches.
7 . The backing plate of claim 1 , wherein the single metallic plate is substantially rectangular.
8 . The backing plate of claim 1 , wherein the single metallic plate is a parallelapiped.
9 . The backing plate of claim 1 , wherein the single metallic plate is oval.
10 . The backing plate of claim 1 , wherein the single metallic plate is circular.
11 . The backing plate of claim 1 , wherein the single metallic plate is triangular.
12 . The backing plate of claim 1 , wherein the single metallic plate is multi-sided.
13 . The backing plate of claim 1 wherein an insulating plate is permanently bonded to a second surface of the single metallic plate
14 . A method of forming a cooling backing plate for a sputtering target, comprising:
machining a single plate of material to form a smooth, flat first surface for mounting a sputtering target;
forming through-holes through the single sheet in directions parallel with the smooth, flat first surface; and
positioning plugs within the through holes so as to form that cooling channels are formed within the single sheet of material.
15 . The method of claim 14 , wherein forming through-holes includes gun-drilling holes through an edge of the single plate of material.
16 . The method of claim 14 , wherein forming through-holes includes laser ablation machining through an edge of the single plate of material.
17 . The method of claim 14 , wherein forming through-holes includes electrodischarge machining through an edge of the single plate of material.
18 . The method of claim 14 , further including bonding an insulating plate on a second surface of the single plate of material opposite the first surface of the single plate of material.
19 . A target assembly, comprising:
a backing plate, comprising:
a single metallic plate;
cooling channels formed laterally within the single metallic plate, the cooling channels being formed through the single metallic plate; and
plugs positioned in the cooling channels so as to seal and form cooling passages within the single metallic plate; and
a sputtering target bonded to a first surface of the backing plate.
20 . The target assembly of claim 19 , further including an insulating plate permanently bonded to a second surface of the backing plate, the second surface opposite the first surface.