Toto Ltd.

Other

Ulvac, Inc.

Anelva Co.

Tetsuo Kitabayashi

Toshiya Watanabe

Osamu Okamoto

Jun Miyaji

Koh Fuwa

Noriaki Tateno

Hiroaki Hori

Takeshi Uchimura

Yasumi Sago

Masami Sasaki

Ken Maehira

Ken Maehara

Jun Miyagi

Atsushi Obara

The object of the present invention is to provide an electrostatic chuck in which the surface can be kept smooth after being exposed to plasma, so as to protect a material to be clamped such as a silicon wafer from being contaminated with particles, and which is excellent in clamping and releasing a material to be clamped. According to the present invention, there is provided an electrostatic chuck comprising a dielectric material in which alumina is 99.4 wt % or more, titanium oxide is more than 0.2 wt % and equal to or less than 0.6 wt %, whose average particle diameter is 2 &#x3bc;m or less, and whose volume resistivity is 10-10&#x3a9;cm in room temperature, wherein the electrostatic chuck is used in a low temperature of 100&#xb0; C or less.

Electrostatic chuck

The object of the present invention is to provide an electrostatic chuck in which the surface can be kept smooth after being exposed to plasma, so as to protect a material to be clamped such as a silicon wafer from being contaminated with particles, and which is excellent in clamping and releasing a material to be clamped. According to the present invention, there is provided an electrostatic chuck comprising a dielectric material in which alumina is 99.4 wt % or more, titanium oxide is more than 0.2 wt % and equal to or less than 0.6 wt %, whose average particle diameter is 2 &#x3bc;m or less, and whose volume resistivity is 10-10&#x3a9;cm in room temperature, wherein the electrostatic chuck is used in a low temperature of 100&#xb0; C. or less.

An electrostatic chuck for attracting an insulative substrate to be processed, the electrostatic chuck comprising a dielectric layer having a first surface which attracts an insulative substrate, and a second surface on which are provided a plurality of electrodes, and an insulative support base plate fixing said dielectric layer. A distance between adjacent ones of the electrodes and the thickness of the dielectric layer are adjusted such that when a potential difference is established between the electrodes, a non-uniform electric field is formed in which the insulative substrate is partially polarized and attracted to the first surface by gradient force.

Electrostatic chuck for an electrically insulative substrate, and a method of using same

According to the present invention, there is provided an electrostatic chuck for electrostatically attracting an insulative substrate, an apparatus for heating/cooling an insulative substrate using the electrostatic chuck, and a method for controlling the temperature of an insulative substrate. The shape and the properties of the dielectric, and the shape of the electrodes, which form the electrostatic chuck, are disclosed. Also the apparatus for heating/cooling an insulative substrate comprising a plate, a gas supply conduit and a temperature controlling system, and the apparatus for processing an insulative substrate in which the apparatus for heating/cooling an insulative substrate is installed are disclosed.

Electrostatic chuck and processing apparatus for insulative substrate

An electrostatic chuck for electrostatically clamping a semiconductor wafer while minimizing any plane temperature difference thereof has a dielectric layer joined to a metal plate and an inner electrode disposed in the di-electric layer. The dielectric layer has a raised outer rim disposed on an upper surface thereof along an outer peripheral edge thereof, and a plurality of protrusions disposed on the upper surface radially inwardly of the outer rim, the protrusions having upper surfaces for clamping the semiconductor wafer in direct contact therewith. The volume resistivity of the dielectric layer is 10.sup.9 .OMEGA.m or less, and Rmax (maximum height) of the clamping surfaces of the protrusions 5 is 2.0 .mu.m or less and or Ra (center-line average roughness) thereof is 0.25 .mu.m or less. The ratio of the total area of the clamping surfaces of the protrusions to the entire area of the upper surface of the dielectric layer is equal to or greater than 1% and less than 10%.

Electrostastic chuck

An electrostatic chuck having an insulating layer comprising solid-solution grains comprised of alumina and a transition metal oxide having the structure of a corundum, and a glass component present in grain boundaries of the solid-solution grains. The transition metal oxide is a transition metal oxide capable of forming a solid solution with alumina, and preferably includes chromia (Cr.sub.2 O.sub.3), whose crystal structure is similar to alumina, having the structure of a corundum. The electrostatic chuck can exhibit a stable electrostatic performance without regard to operating temperatures.

An electrostatic chuck has a substrate, an insulating layer disposed on the substrate for attracting a workpiece thereto, and an electrode interposed between the substrate and the insulating layer. The insulating layer having a volume resistivity .rho.(.OMEGA.m), a dielectric constant .epsilon..sub.r, and a thickness d (m), and being spaced from the workpiece which is attracted thereto by a gap having a distance .delta.(m). The volume resistivity .rho., the dielectric constant .epsilon..sub.r, the thickness d, and the distance .delta. satisfy the following relationship:

An electrostatic chuck for electrostatically attracting and holding an object such as a semiconductor wafer includes a base plate, at least two layers each including an electrically insulating film and an electrode attached to a lower surface thereof, the at least two layers being disposed as attractive layers on the base plate, and a voltage applying assembly for selectively applying a voltage to at least one of the electrodes to electrostatically attract the object to the insulating film of an uppermost one of the layers. The insulating films may have different insulation resistances to allow for a wider range of temperature changes.

A first voltage is first applied to the electrode or electrodes of an electrostatic chuck for electrostatically attracting a workpiece such as a silicon wafer. Then, before the workpiece is removed from the electrostatic chuck, a second voltage which is of opposite polarity to the first voltage is applied to the electrostatic chuck for eliminating a residual attractive force from the electrostatic chuck. The second voltage has a voltage value which is 1.5 to 2 times higher than the voltage value of the first voltage. The second voltage is continuously applied for a period of time which is in inverse proportion to the voltage value of the second voltage.

Growing community of inventors

Fukuoka, Japan

Tetsuo Kitabayashi