International Business Machines Corporation

Robert E Tompkins

Robert P Westerfield, Jr

Joseph S Logan

Raymond R Ruckel

Michael S Barnes

John H Keller

An electrostatic chuck is disclosed that is resistant to the formation of vacuum arcs between the back of the wafer being processed and the body of the chuck. A guard ring surrounds the chuck and floats close to the self-bias potential induced by the plasma on the wafer. The voltage between the wafer and the closest electrode is thereby capacitively divided by the guard ring.

Guard ring electrostatic chuck

An electrostatic chuck has its electrodes biased with respect to the self-bias potential induced by the plasma on the wafer, thereby providing improved resistance to breakdown in spite of variation of the wafer potential during processing. An alternate embodiment further suppresses the formation of vacuum arcs between the back of the wafer being processed and the body of the chuck by the interposition of a conductive guard ring at the self-bias potential, thereby defining an equipotential area between the closest electrode and the wafer.

Electrostatic chuck with reference electrode

An electrostatic chuck is made by a method in which the component parts are machined, then anodized to provide a hard insulating surface, and then assembled in a fixture, to provide a planar surface for wafer support that retains superior insulating properties; gas may be fed from the rim only, diffusing within interstices between the clamping surface and the wafer and maintaining a desired pressure by flowing radially through an impedance determined by the average spacing between clamping surface and wafer, thereby providing uniform pressure across the clamping surface without the use of elastomeric seals.

Method of making electrostatic chuck with oxide insulator

An aluminum electrostatic chuck for holding semiconductor wafers during wafer processing. The chuck is characterized by a closely determined magnitude of electrostatic holding force due to an anodization step for creating a finely uniform thickness of dielectric material on the chuck surface facing the wafer which, in turn, determines the holding force. The chuck cross section comprises two different thickness areas with fluid cooling being applied to the thinner thickness area during chuck anodization to assure thickness uniformity of the anodized material across the face of the chuck.

Electrostatic chuck having relatively thick and thin areas and means for

An electrostatic chuck has its electrodes biased with respect to the self-bias potential induced by the plasma on the wafer, thereby providing improved resistance to breakdown in spite of variation of the wafer potential during processing, further suppressing the formation of vacuum arcs between the back of the wafer being processed and the body of the chuck by the interposition of a conductive guard ring at the self-bias potential, thereby defining an equipotential area between the closest electrode and the wafer.

An electrostatic chuck suppresses the formation of vacuum arcs between the back of the wafer being processed and the body of the chuck by the interposition of a guard ring that floats close to the self-bias potential induced by the plasma on the wafer, thereby capacitively dividing the voltage between the wafer and the closest electrode.

An electrostatic chuck 8 assembly includes, from top to bottom: a top multilayer ceramic insulating layer 10; an electrostatic pattern layer 12 having a conductive electrostatic pattern 16 disposed on a multilayer ceramic substrate; a multilayer ceramic support layer 20; and, a heat sink base 30 having a backside cooling channels machined therein. Layers 12, 12 and 20 are bonded together using multilayer ceramic techniques and the heatsink base 30 is brazed to the bottom of the multilayer ceramic support layer 20.

Ceramic electrostatic chuck

An electrostatic chuck 40 assembly includes, from top to bottom: a top isolation layer 42; an electrostatic pattern layer 44 comprised of an electrically conductive electrostatic pattern 46 disposed on a substrate 45; a heating layer 50 comprised of an electrically conductive heating pattern 54 disposed on a substrate 52; a support 60; and, a heat sink base 70 having backside cooling and insulating channels 78, 80 provided therein.

Temperature cycling ceramic electrostatic chuck

An electrostatic chuck is provided with an electrode split into two sections. The separate sections are joined through a tapered joint and bonded using epoxy. An insulator electrically separates the two sections and covers the top of the joined sections to form a clamping surface. The geometry of the electrode forms three annular regions, dividing the clamping surface into two equal areas distributed symmetrically. Moreover, the split-ring electrostatic chuck just described is fabricated by forming the two, separate electrodes; coating the separate electrodes with an insulator; joining the electrodes; machining the joint, top surface of the electrodes to form a single, co-planar, flat, smooth surface; and applying an insulator to that top surface.

Growing community of inventors

Pleasant Valley, NY, United States of America

Robert E Tompkins