Electrostatic chucks (ESCs) for reactor or plasma processing chambers, and methods of fabricating ESCs, are described. In an example, a substrate support assembly includes a ceramic bottom plate having heater elements therein, the ceramic bottom plate composed of alumina having a first purity. The substrate support assembly also includes a ceramic top plate having an electrode therein, the ceramic top plate composed of alumina having a second purity higher than the first purity. A bond layer is between the ceramic top plate and the ceramic bottom plate. The ceramic top plate is in direct contact with the bond layer, and the bond layer is in direct contact with the ceramic bottom plate.

An electrostatic chuck includes a first ceramic member disk-shaped and having an annular step surface outside a circular wafer holding surface thereof, the annular step surface being at a lower level than the wafer holding surface, the first ceramic member having a volume resistivity that allows Coulomb force to be exerted; a first electrode embedded in the first ceramic member at a position facing the wafer holding surface; a second electrode disposed on the annular step surface of the first ceramic member, the second electrode being independent of the first electrode; and a second ceramic member having an annular shape and configured to cover the annular step surface having the second electrode thereon, the second ceramic member having a volume resistivity that allows Johnsen-Rahbek force to be exerted, wherein an upper surface of the second ceramic member is a focus ring holding surface on which a focus ring is placed.

An electrostatic chuck includes a first ceramic member disk-shaped and having an annular step surface outside a circular wafer holding surface thereof, the annular step surface being at a lower level than the wafer holding surface, the first ceramic member having a volume resistivity that allows Coulomb force to be exerted; a first electrode embedded in the first ceramic member at a position facing the wafer holding surface; a second electrode disposed on the annular step surface of the first ceramic member, the second electrode being independent of the first electrode; and a second ceramic member having an annular shape and configured to cover the annular step surface having the second electrode thereon, the second ceramic member having a volume resistivity that allows Johnsen-Rahbek force to be exerted, wherein an upper surface of the second ceramic member is a focus ring holding surface on which a focus ring is placed.

Described are electrostatic chucks that are useful to support a workpiece during a step of processing the workpiece, the electrostatic chuck including embossments that are made of multiple deposited layers, the layers including diamond-like carbon layers and layers that contain silicon-based materials such as silicon carbide layers.

Described are electrostatic chucks that are useful to support a workpiece during a step of processing the workpiece, the electrostatic chuck including embossments that are made of multiple deposited layers, the layers including diamond-like carbon layers and layers that contain silicon-based materials such as silicon carbide layers.

A magnetic base for an electric machine tool, in particular for a magnetic core drilling machine. A body that is accommodated in a receiving space. At least one first magnet coil constituting an electromagnet, a coil winding of the at least one first magnet coild being wound on a bobbin and a magnetic force of which is switchable between a maximum resultant holding force and a minimum resultant holding force. The coil winding of the magnet coil has two end sections that are each connected to a connecting cable that serves to make electrical contact between the magnetic coil and the electric machine tool. The body has a first side adapted to be coupled to the electric machine tool and has an opposite second side adapted to be placed on a workpiece that is to be processed. End sections of the coil winding are connected to the connecting cables.

An electrostatic chuck device includes: a mounting table provided with a mounting surface; a focus ring; and a cooling element, in which a holding portion of the mounting table is provided with an annular groove portion surrounding the mounting table, a through-hole that is open on a bottom surface of the groove portion, upper surfaces on both sides of the groove portion in a width direction in the holding portion form a holding surface that comes into contact with the focus ring and holds the focus ring, the holding surface is composed of an inner peripheral surface located further on an inner periphery side than the groove portion and an outer peripheral surface located further on an outer periphery side than the groove portion, and the holding surface satisfies the following conditions (i) and (ii), wherein (i) the holding surface has a shape in which in a cross section in a thickness direction, a straight line connecting a first point corresponding to an innermost periphery of the holding surface and a second point corresponding to an outermost periphery of the holding surface has a positive inclination or a negative inclination from the first point corresponding to the innermost periphery toward the second point corresponding to the outermost periphery, and satisfies 0≤| in the cross section of the holding surface in the thickness direction, a height of the first point corresponding to the innermost periphery−a height of the second point corresponding to the outermost periphery |≤10 μm, (ii) a leak area of the inner peripheral surface and a leak area of the outer peripheral surface are less than 0.7 mm.sup.2.

An electrostatic chuck device includes: a mounting table provided with a mounting surface; a focus ring; and a cooling element, in which a holding portion of the mounting table is provided with an annular groove portion surrounding the mounting table, a through-hole that is open on a bottom surface of the groove portion, upper surfaces on both sides of the groove portion in a width direction in the holding portion form a holding surface that comes into contact with the focus ring and holds the focus ring, the holding surface is composed of an inner peripheral surface located further on an inner periphery side than the groove portion and an outer peripheral surface located further on an outer periphery side than the groove portion, and the holding surface satisfies the following conditions (i) and (ii), wherein (i) the holding surface has a shape in which in a cross section in a thickness direction, a straight line connecting a first point corresponding to an innermost periphery of the holding surface and a second point corresponding to an outermost periphery of the holding surface has a positive inclination or a negative inclination from the first point corresponding to the innermost periphery toward the second point corresponding to the outermost periphery, and satisfies 0≤| in the cross section of the holding surface in the thickness direction, a height of the first point corresponding to the innermost periphery−a height of the second point corresponding to the outermost periphery |≤10 μm, (ii) a leak area of the inner peripheral surface and a leak area of the outer peripheral surface are less than 0.7 mm.sup.2.

A holding device manufacturing method includes a step of preparing a first joined body which includes a pre-machining ceramic member having a first surface and a fifth surface located opposite the first surface and approximately parallel to the first surface, a base member, and a joining portion disposed between the first surface of the pre-machining ceramic member and a third surface of the base member and joining the pre-machining ceramic member and the base member together. The thickness of the joining portion of the first joined body in a first direction, in which the first surface and the third surface face each other via the joining portion, increases from one end side toward the other end side of the joining portion in a second direction perpendicular to the first direction. The method includes a step of machining the fifth surface of the pre-machining ceramic member in the first joined body.

A holding device manufacturing method includes a step of preparing a first joined body which includes a pre-machining ceramic member having a first surface and a fifth surface located opposite the first surface and approximately parallel to the first surface, a base member, and a joining portion disposed between the first surface of the pre-machining ceramic member and a third surface of the base member and joining the pre-machining ceramic member and the base member together. The thickness of the joining portion of the first joined body in a first direction, in which the first surface and the third surface face each other via the joining portion, increases from one end side toward the other end side of the joining portion in a second direction perpendicular to the first direction. The method includes a step of machining the fifth surface of the pre-machining ceramic member in the first joined body.