High temperature electrostatic chuck bonding adhesive
Methods and apparatus for bonding an electrostatic chuck to a component of a substrate support are provided herein. In some embodiments, an adhesive for bonding components of a substrate support may include a matrix of silicon-based polymeric material having a filler dispersed therein. The silicon based polymeric material may be a polydimethylsiloxane (PDMS) structure having a molecular weight with a low molecular weight (LMW) content Σ D3-D10 of less than about 500 ppm. In some embodiments, the filler may comprise between about 50 to about 70 percent by volume of the adhesive layer. In some embodiments, the filler may comprise particles of aluminum oxide (Al 2 O 3 ), aluminum nitride (AlN), yttrium oxide (Y 2 O 3 ), or combinations thereof. In some embodiments, the filler may comprise particles having a diameter of about 10 nanometers to about 10 microns.
1. A substrate support, comprising:
a base;
an adhesive layer comprising a matrix of silicon-based polymeric material having a filler dispersed therein, wherein the matrix is formed of a silicon-based polymeric material having a molecular weight with a low molecular weight (LMW) content Σ D3-D10 of less than about 500 ppm; and
an electrostatic chuck disposed atop the base and the adhesive layer, wherein the adhesive layer bonds the base and the electrostatic chuck.
2. The substrate support of claim 1 , wherein the base comprises one of aluminum, stainless steel, ceramic, or aluminum-ceramic composite.
3. The substrate support of claim 1 , further comprising:
a baffle assembly disposed proximate the base, wherein the baffle assembly is configured to hold one of a process kit or a process shield.
4. The substrate support of claim 1 , wherein the silicon-based polymeric material comprises a polydimethylsiloxane (PDMS) structure having a repeating dimethylsiloxane unit.
5. The substrate support of claim 1 , wherein the adhesive layer is about 0.004 to about 0.015 inches thick.
6. The substrate support of claim 1 , wherein the adhesive layer has a metal content of less than about 1 percent.
7. The substrate support of claim 1 , wherein the adhesive layer is substantially non-reactive with halogen containing chemistries.
8. The substrate support of claim 1 , wherein the adhesive layer is operable at a temperature of between about 120 degrees Celsius and about 180 degrees Celsius.
9. The substrate support of claim 1 , wherein the adhesive layer has a thermal conductivity of at least about 0.5 W/mK.
10. The substrate support of claim 1 , wherein the filler comprises between about 50 to about 70 percent by volume of the adhesive layer.
11. The substrate support of claim 10 , wherein the filler comprises particles of aluminum oxide (Al 2 O 3 ), aluminum nitride (AlN), yttrium oxide (Y 2 O 3 ), or combinations thereof.
12. The substrate support of claim 10 , wherein the filler comprises particles having a diameter of about 10 nanometers to about 10 microns.
13. A method of bonding a substrate support to an electrostatic chuck, comprising:
depositing an adhesive layer comprising a matrix of silicon based polymeric material having a filler dispersed therein atop a substrate support base, wherein the silicon based polymeric matrix is formed of a polymeric material having a molecular weight with a low molecular weight (LMW) content Σ D3-D10 of less than about 500 ppm; and
bonding an electrostatic chuck to the substrate support base with the adhesive layer.
14. The method of claim 13 , wherein the silicon based polymeric material comprises a polydimethylsiloxane (PDMS) structure having a repeating dimethylsiloxane unit.
15. The method of claim 13 , wherein the filler comprises between about 50 to about 70 percent by volume of the adhesive layer.
16. The method of claim 15 , wherein the filler comprises particles of aluminum oxide (Al 2 O 3 ), aluminum nitride (AlN), yttrium oxide (Y 2 O 3 ), or combinations thereof.
17. The method of claim 15 , wherein the filler comprises particles having a diameter of about 10 nanometers to about 10 microns.
18. The method of claim 13 , wherein bonding the electrostatic chuck to the substrate support base comprises:
applying a pressure of about 0.5 to about 14.5 psi between the electrostatic chuck and the base while heating at least one of the base or adhesive layer to a predetermined temperature.
19. The method of claim 13 , wherein the bonding process is performed in a pressure vessel at a pressure of about 50 to about 200 psi.
20. The method of claim 13 , further comprising:
heating at least one of the base or the electrostatic chuck to a temperature of about 50 to about 110 degrees Celsius prior to depositing the adhesive layer.
21. The method of claim 13 , further comprising:
applying a metal organosilane primer to an adhesive-contacting surface of either or both of the electrostatic chuck and the base.
22. The method of claim 13 , further comprising:
heating the electrostatic chuck, adhesive layer and base, after bonding, to a temperature of between about 10 to 30 degrees Celsius above a bonding temperature to at least partially remove lower molecular weight residues from the adhesive layer.
23. A substrate support, comprising:
a base;
an adhesive layer comprising a matrix of silicon-based polymeric material having a filler dispersed therein, wherein the silicon-based polymeric material comprises a polydimethylsiloxane (PDMS) structure having a repeating dimethylsiloxane unit; and
an electrostatic chuck disposed atop the base and the adhesive layer, wherein the adhesive layer bonds the base and the electrostatic chuck.