Guard wafer for semiconductor structure fabrication
View Patent ↗An apparatus (and method for operating the same) which allows tightly coupling the device wafer to the electrostatic chuck of the process chamber after the process chamber is conditioned. The method comprises (a) providing (i) a process chamber and (ii) an electrostatic chuck in the process chamber; (b) placing a guard wafer on the electrostatic chuck via a top surface of the electrostatic chuck; and (c) forming a particle restraining layer on essentially all surfaces that are exposed to the ambient inside the process chamber, wherein the particle restraining layer has a thickness in a first direction of at least 500 Å, wherein the first direction is essentially perpendicular to an interfacing surface between the particle restraining layer and an inner surface of the process chamber, and wherein the guard wafer comprises a material selected from the group consisting of a metal and a semiconductor oxide.
1. An apparatus operation method, comprising:
providing (i) a process chamber and (ii) a chuck in the process chamber;
placing a guard wafer on and in direct physical contact with the chuck via a top surface of the chuck; and
forming a particle restraining layer on essentially all surfaces that are exposed to the ambient inside the process chamber,
wherein the particle restraining layer has a thickness in a first direction of at least 500 nm,
wherein the first direction is essentially perpendicular to an interfacing surface between the particle restraining layer and the chuck, and
wherein the guard wafer comprises a material selected from the group consisting of a metal and a semiconductor oxide.
2. The method of claim 1 , wherein the guard wafer comprises essentially aluminum.
3. The method of claim 1 , wherein the guard wafer comprises an aluminum alloy.
4. The method of claim 1 , wherein the guard wafer comprises an alloy not including aluminum.
5. The method of claim 1 , wherein the guard wafer comprises an iron alloy.
6. The method of claim 1 , wherein the guard wafer comprises a semiconductor oxide.
7. The method of claim 6 , wherein the semiconductor oxide comprises silicon dioxide.
8. The method of claim 1 , further comprising:
removing the guard wafer from the chuck; and
placing a first device wafer on and in direct physical contact with the top surface of the chuck for processing,
wherein the first device wafer comprises first electrical devices.
9. The method of claim 8 , further comprising, after said placing the first device wafer is performed, forming a metal thin film on top of the first device wafer.
10. The method of claim 9 , further comprising, after said forming the metal thin film is performed:
removing the first device wafer; and then
placing a second device wafer on and in direct physical contact with the top surface of the chuck,
wherein the second device wafer comprises second electrical devices.
11. The method of claim 10 , further comprising, after said placing the second device wafer is performed, forming another metal thin film on top of the second device wafer.
12. The method of claim 9 , further comprising, after said forming the metal thin film is performed:
removing the first device wafer; then
placing another guard wafer on and in direct physical contact with the top surface of the chuck.
13. The method of claim 1 , further comprising, before said placing the guard wafer on and in direct physical contact with the chuck, baking the guard wafer in a degas chamber.