CMP Polisher Head Over-Rotation Restrictor with Vertical Lift Force

Abstract

A CMP tool including a polisher head has a floating head assembly configured to be driven around a rotational axis an upper head assembly disposed within the upper head assembly. An over-rotation limiting pin projects between the floating head assembly and the upper head assembly. A restrictor/lifter receptacle is located to receive the over-rotation limiting pin, the restrictor/lifter receptacle having opposing vertical sidewalls with different length, and a sloped top sidewall.

What is claimed is: 
     
         1 . A chemical-mechanical planarization (CMP) polisher head, comprising:
 a floating head assembly configured to be driven around a rotational axis; and   an upper head assembly disposed within the upper head assembly;   an over-rotation limiting pin projecting between the floating head assembly and the upper head assembly; and   a restrictor/lifter receptacle located to receive the over-rotation limiting pin, the restrictor/lifter receptacle having a lateral width greater than a diameter of the over-rotation limiting pin.   
     
     
         2 . The CMP polisher head as recited in  claim 1 , further comprising an annular rolling seal between the floating head assembly and the upper head assembly. 
     
     
         3 . The CMP polisher head as recited in  claim 2 , wherein the over-rotation limiting pin floats within the restrictor/lifter receptacle when the floating head assembly and the upper head assembly are in rotational equilibrium. 
     
     
         4 . The CMP polisher head as recited in  claim 1 , wherein the over-rotation limiting pin is one of a plurality of over-rotation limiting pins asymmetrically positioned around the upper head assembly. 
     
     
         5 . The CMP polisher head as recited in  claim 1 , wherein the restrictor/lifter receptacle has first and second opposing vertical sides, the first vertical side having a first length and the second vertical side having a greater second length. 
     
     
         6 . The CMP polisher head as recited in  claim 1 , wherein the restrictor/lifter receptacle has a curvilinear top surface. 
     
     
         7 . The CMP polisher head as recited in  claim 1 , wherein the restrictor/lifter receptacle is formed within the floating head assembly. 
     
     
         8 . The CMP polisher head as recited in  claim 1 , wherein the over-rotation limiting pin and the restrictor/lifter receptacle are configured to provide a translating force on the floating head assembly when the angular velocity of the upper head assembly exceeds the angular velocity of the floating head assembly. 
     
     
         9 . A chemical-mechanical planarization (CMP) tool, comprising:
 a CMP polisher head configured to rotate around a first rotational axis;   a platen having a polishing pad disposed thereon, the platen configured to rotate around a second rotational axis; and   a slurry dispenser positioned proximate to the platen, the slurry dispenser operative to controllably deliver a slurry material on the polishing pad, wherein the CMP polisher head comprises:
 a first rotational component having a flange for mounting to a spindle driven by a motor around the first rotational axis, the first rotational component having a rolling seal affixed proximate to a bottom terminus thereof; and 
 a second rotational component axially aligned with the first rotational component along the first rotational axis, the second rotational component attached to the first rotational component by engaging in a compressive arrangement with the rolling seal, wherein an over-rotation limiting pin and a restrictor/lifter receptacle are provided with the first and second rotational components such that the over-rotation limiting pin and the restrictor/lifter receptacle operate, when respectively engaged, to provide a translation force to translate the second rotational component relative to the first rotational component along the first rotational axis. 
   
     
     
         10 . The CMP tool as recited in  claim 9 , wherein the over-rotation limiting pin is one of a plurality of over-rotation limiting pins positioned along a circular perimeter of an outer wall of the first rotational component and a corresponding plurality of receptacles are positioned in an inner wall of the second rotational component. 
     
     
         11 . The CMP tool as recited in  claim 9 , wherein the over-rotation limiting pin floats within the restrictor/lifter receptacle when the first rotational component and the second rotational component are in rotational equilibrium. 
     
     
         12 . The CMP tool as recited in  claim 9 , wherein the over-rotation limiting pin is one of a plurality of over-rotation limiting pins asymmetrically positioned around the first rotational component. 
     
     
         13 . The CMP tool as recited in  claim 9 , wherein the restrictor/lifter receptacle has first and second opposing vertical sides, the first vertical side having a first length and the second vertical side having a greater second length. 
     
     
         14 . The CMP tool as recited in  claim 9 , wherein the restrictor/lifter receptacle has a curvilinear top surface. 
     
     
         15 . The CMP tool as recited in  claim 9 , wherein the restrictor/lifter receptacle is formed within the second rotational component. 
     
     
         16 . The CMP tool as recited in  claim 9 , wherein the over-rotation limiting pin and the restrictor/lifter receptacle are configured to provide a translating force on the second rotational component when the angular velocity of the first rotational component exceeds the angular velocity of the second rotational component. 
     
     
         17 . A method of manufacturing an integrated circuit, comprising:
 polishing a material layer over a semiconductor substrate, the polishing including applying a force between an upper head assembly of a CMP tool and a polishing pad;   lifting the semiconductor substrate off of the polishing pad; and   simultaneous with the lifting, applying a translating force between the upper head assembly and a floating head assembly via an over-rotation limiting pin projecting between the floating head assembly and the upper head assembly and a restrictor/lifter receptacle located to receive the over-rotation limiting pin.   
     
     
         18 . The method as recited in  claim 17 , wherein the over-rotation limiting pin is one of a plurality of over-rotation limiting pins asymmetrically positioned around the upper head assembly. 
     
     
         19 . The method as recited in  claim 17 , wherein the restrictor/lifter receptacle has a curvilinear upper surface. 
     
     
         20 . The method as recited in  claim 17 , wherein the restrictor/lifter receptacle has a lateral width greater than a diameter of the over-rotation limiting pin.