Abstract: Apparatus and method for inductively coupling electrical power to a plasma in a semiconductor process chamber. In a first aspect, an array of wedge-shaped induction coils are distributed around a circle. The sides of adjacent coils are parallel, thereby enhancing the radial uniformity of the magnetic field produced by the array. In a second aspect, electrostatic coupling between the induction coils and the plasma is minimized by connecting each induction coil to the power supply so that the turn of wire of the coil which is nearest to the plasma is near electrical ground potential. In one embodiment, the hot end of one coil is connected to the unbalanced output of an RF power supply, and the hot end of the other coil is connected to electrical ground through a capacitor which resonates with the latter coil at the frequency of the RF power supply.

Abstract: A photoresist coater has a rotatable chuck to support a substrate, a source of photoresist, a pivotable dispensing arm extendable over the chuck, and a nozzle at the end of the dispensing arm. The nozzle has an aperture with a dimension sufficiently small that photoresist directed therethrough forms an aerosol which is directed onto the substrate.

Abstract: Apparatus and method for inductively coupling electrical power to a plasma in a semiconductor process chamber. In a first aspect, an array of induction coils is distributed over a geometric surface having a circular transverse section. Each coil has a transverse section which is wedge-shaped so that the adjacent sides of any two adjacent coils in the array are approximately parallel to a radius of the circular transverse section of the geometric surface. The sides of adjacent coils being parallel enhances the radial uniformity of the magnetic field produced by the coil array. In a second aspect, electrostatic coupling between the induction coils and the plasma is minimized by connecting each induction coil to the power supply so that the turn of wire of the coil which is nearest to the plasma is near electrical ground potential. In one embodiment, the near end of each coil connects directly to electrical ground. In second and third embodiments, two coils are connected in series at the near end of each coil.

Abstract: A method of adjusting the cathode DC bias in a plasma chamber for fabricating semiconductor devices. A dielectric shield is positioned between the plasma and a selected portion of the electrically grounded components of the chamber, such as the electrically grounded chamber wall. The cathode DC bias is adjusted by controlling one or more of the following parameters: (1) the surface area of the chamber wall or other grounded components which is blocked by the dielectric shield; (2) the thickness of the dielectric; (3) the gap between the shield and the chamber wall; and (4) the dielectric constant of the dielectric material. In an apparatus aspect, the invention is a plasma chamber for fabricating semiconductor devices having an exhaust baffle with a number of sinuous passages. Each passage is sufficiently long and sinuous that no portion of the plasma within the chamber can extend beyond the outlet of the passage.

Abstract: Apparatus and method for mounting a workpiece support platform or platen within a semiconductor process vacuum chamber to provide electrical or thermal insulation and mechanical stability, but yet minimize mechanical stresses due to differential thermal expansion between the platen and the dielectric spacer. Specifically, the invention includes a workpiece support platen having a rear surface abutting a front surface of a platen-support shelf. The shelf preferably provides electrical or thermal insulation between the platen and the wall of the vacuum chamber. The shelf is attached to the enclosure of the vacuum chamber, but the platen is not rigidly attached to the shelf. Instead, a pressure actuator, such as a spring or pneumatic piston, presses the platen against the shelf. In one embodiment, the pressure actuator can be turned off to allow the platen to expand or contract during periods of heating or cooling, such as when the chamber is turned off or on before or after maintenance.

Abstract: A plasma chamber having a magnet which produces a magnetic field such that, within a region parallel to and adjacent to the workpiece, the direction of the magnetic field is approximately the vector cross product of (i) the gradient of the magnitude of the magnetic field, and (ii) a vector extending perpendicularly from the workpiece surface toward the plasma. Alternatively, the plasma chamber includes a north magnetic pole and a south magnetic pole located at distinct azimuths around the periphery of the workpiece. The azimuth of the south magnetic pole relative to the north magnetic pole is clockwise around the central axis, and each magnetic pole faces a direction which is more toward than away from a central axis of the workpiece area. An additional aspect of the invention is a plasma chamber having a rotating magnetic field produced by electromagnets spaced around the periphery of the workpiece which receive successive fixed amounts of electrical current during successive time intervals.