Wafer polishing machine with fluid bearings and drive systems

In a semiconductor wafer polishing machine of the type comprising at least one polishing pad assembly and at least one wafer holder positioned to hold a semiconductor wafer against the polishing pad assembly, the improvement comprising:

• a support positioned adjacent the polishing pad assembly, at least one of said support and said polishing pad assembly comprising at least one fluid inlet connectable to a source of a fluid at a higher pressure, at least one fluid outlet connectable to a fluid drain at a lower pressure, and at least one bearing surface over which fluid flows from the source to the drain, said polishing pad assembly supported by the fluid over the bearing surface for low-friction movement with respect to the support;
• wherein the polishing pad assembly comprises a polishing pad, a rotatable platen supporting the polishing pad, and bearings coupled to the platen to guide the platen in rotational motion with respect to the support about a rotational axis.

In a semiconductor wafer polishing machine of the type comprising at least one polishing pad assembly and at least one wafer holder positioned to hold a semiconductor wafer against the polishing pad assembly, the improvement comprising:

• a support positioned adjacent the polishing pad assembly, at least one of said support and said polishing pad assembly comprising at least one fluid inlet connectable to a source of a fluid at a higher pressure, at least one fluid outlet connectable to a fluid drain at a lower pressure, and at least one bearing surface over which fluid flows from the source to the drain, said polishing pad assembly supported by the fluid over the bearing surface for low-friction movement with respect to the support;
• wherein each bearing surface is annular, and wherein each fluid inlet is surrounded by the respective fluid bearing surface.

In a semiconductor wafer polishing machine of the type comprising at least one polishing pad assembly and at least one wafer holder positioned to hold a semiconductor wafer against the polishing pad assembly, the improvement comprising:

• a support positioned adjacent the polishing pad assembly, said support comprising at least one fluid inlet connectable to a source of a fluid at a high pressure, at least one fluid outlet connectable to a fluid drain at a lower pressure, and at least one bearing surface over which fluid flows from the source to the drain, said polishing pad assembly supported by the fluid over the bearing surface for low-friction movement with respect to the support;
• wherein the support holds a plurality of tubes, each tube comprising an exposed annular end surface, wherein each fluid inlet is positioned within the respective tube, and wherein each bearing surface comprises the annular end surface of the respective tube.

In a semiconductor wafer polishing machine of the type comprising at least one polishing pad assembly and at least one wafer holder positioned to hold a semiconductor wafer against the polishing pad assembly, the improvement comprising:

• a support positioned adjacent the polishing pad assembly, at least one of said support and said polishing pad assembly comprising at least one fluid inlet connectable to a source of a fluid at a higher pressure, at least one fluid outlet connectable to a fluid drain at a lower pressure, and at least one bearing surface over which fluid flows from the source to the drain, said polishing pad assembly supported by the fluid over the bearing surface for low-friction movement with respect to the support;
• wherein said polishing pad assembly comprises at least one polishing pad and a platen supporting the polishing pad, said platen comprising a hemispherical surface;
• wherein the at least one bearing surface comprises a plurality of bearing surfaces arranged around a hemispherical recess in the support, said recess receiving the hemispherical surface to form a ball joint.

In a semiconductor wafer polishing machine of the type comprising at least one polishing pad assembly and at least one wafer holder positioned to hold a semiconductor wafer against the polishing pad assembly, the improvement comprising:

• said wafer holder comprising a support comprising a hemispherical recess and a wafer chuck comprising a hemispherical surface received within the hemispherical recess to form a ball joint;
• at least one of the hemispherical surface and the hemispherical recess comprising at least one fluid inlet connectable to a source of fluid at a higher pressure, at least one fluid outlet connectable to a fluid drain at a lower pressure, and at least one bearing surface over which fluid flows from the source to the drain, said hemispherical surface supported by the fluid over the bearing surface for low-friction rotation with respect to the support about a center of rotation.

In a semiconductor wafer polishing machine of the type comprising at least one polishing pad assembly and at least one wafer holder positioned to hold a semiconductor wafer against the polishing pad assembly, the improvement comprising:

• said wafer holder comprising a support comprising a hemispherical recess and a wafer chuck comprising a hemispherical surface received within the hemispherical recess to form a ball joint;
• said wafer chuck comprising an array of fluid deflectors;
• said support comprising an array of fluid inlets positioned to direct fluid at the fluid deflectors to apply torque to the wafer chuck.