Monolithic substrate support having porous features and methods of forming the same
A method of forming a substrate support for use in a processing chamber includes forming a porous region in each of a plurality of ceramic green sheets, stacking the plurality of ceramic green sheets, each having the porous region formed therein, to form a ceramic laminate, and sintering the ceramic laminate to form a monolithic ceramic body having a porous plug formed therein. The porous plug includes the porous regions in the plurality of ceramic green sheets that are sintered.
1 . A method of forming a substrate support for use in a processing chamber, the method comprising:
micro-machining holes through each of a plurality of ceramic green sheets in a first direction, wherein each hole in each of the plurality of ceramic green sheets extends in the first direction;
forming a ceramic laminate by stacking the plurality of ceramic green sheets, wherein an un-filled hole in each of the plurality of ceramic green sheets is connected to an un-filled hole in an adjacent ceramic green sheet of the plurality of ceramic green sheets in the first direction; and
forming a monolithic ceramic body by sintering the ceramic laminate.
2 . The method of claim 1 , wherein the holes each have a diameter of between 0.1 μm and 100 μm.
3 . The method of claim 1 , wherein the micro-machining comprises drilling, laser ablation, or mask assisted bead blasting.
4 . The method of claim 1 , wherein each of the plurality of ceramic green sheets has a thickness of between 5 μm and 1 mm.
5 . The method of claim 1 , wherein regions with the holes formed therein in adjacent ceramic green sheets in the ceramic laminate have an overlap.
6 . The method of claim 1 , wherein the sintering the ceramic laminate comprises co-firing the ceramic laminate at a firing temperature of between about 600° C. and about 1800° C.
7 . A method of forming a substrate support for use in a processing chamber, the method comprising:
micro-machining first holes through a first dielectric body in a first direction, first recesses in a first surface of the first dielectric body, second holes through a second dielectric body in the first direction, and second recesses in a second surface of the second dielectric body; and
aligning each of the first recesses with a respective one of the second recesses, and each of the first holes with a respective one of the second holes, and bonding the first dielectric body and the second dielectric body.
8 . The method of claim 7 , wherein the first and second dielectric bodies are sintered ceramic bodies comprising ceramic material selected from alumina, aluminum nitride, sapphire, and zirconia.
9 . The method of claim 8 , wherein the bonding of the first dielectric body and the second dielectric body comprises a diffusion bonding process or a glass frit bonding process.
10 . The method of claim 7 , wherein the first and second dielectric bodies are ceramic green bodies comprising ceramic material selected from alumina, aluminum nitride, sapphire, zirconia, and resin material.
11 . The method of claim 10 , wherein the bonding of the first dielectric body and the second dielectric body comprises laminating and sintering the first dielectric body and the second dielectric body.