Sony Corporation

Materials Research Corporation

Tokyo Electron Limited

Other

Tokyo Electron Arizona Inc.

Alexander D Lantsman

Thomas J Licata

James A Seirmarco

Robert Bayer

Apparatus and method for sputter depositing a layer of material comprises a sputtering chamber having an internal conductive wall which provides an electrical reference for plasma during sputter deposition. A conductive shield positioned in the processing space of the chamber between the target and the substrate is configured for capturing sputtered material which would deposit on the chamber wall surface during sputter deposition. The conductive shield reduces the amount of sputtered material depositing on the chamber wall and maintains a surface portion of the wall as a generally stable electrical reference for the plasma and is further operable for passing plasma therethrough during deposition to contact the stable electrical reference.

Apparatus and method for sputter depositing dielectric films on a substrate

DC plasma power supply for a sputter deposition of material layers on a substrate includes a plasma controller and a plasma input for the settings of the output voltage and output current providing plasma ignition and termination with no arcing and no striking voltage. Pre-defined voltages are applied in the vacuum state before sputtering and after sputtering until vacuum is restored in a sputtering apparatus.

DC plasma power supply for a sputter deposition

The specification discloses a power supply circuit which reduces oscillations generated upon ignition of a plasma within a processing chamber. A secondary power supply pre-ignites the plasma by driving the cathode to a process initiation voltage. Thereafter, a primary power supply electrically drives the cathode to generate plasma current and deposition on a wafer.

Soft plasma ignition in plasma processing chambers

An ionized physical vapor deposition apparatus is provided with an RF coil that surrounds the space between a target and a substrate holder and is energized with RF energy, preferably in the 0.1 to 60 MHz range, to form a secondary plasma in a volume of the space between the substrate holder and the main plasma that is adjacent the target. A dielectric material, such as a quartz window, either in the wall of the chamber or inside the chamber, or insulation on the coil, protects the coil from adverse interaction with plasma. Shields between the space and the dielectric material prevent sputtered particles from forming a coating on the dielectric material. The shields are partitioned to prevent eddy currents. The shields may be biased to control contamination and may be commonly or individually biased to optimize the uniformity of coating on the substrate and the directionality of the flux of ionized material at the substrate.

Method and apparatus for ionized sputtering

Sputtering processes are carried out at low pressure, of less than one milli-Torr, particularly in the range of 0.05 to 0.5 mTorr, to reduce scattering of the sputtered particles due to collisions with atoms of the process gas, particularly for coating contacts at the bottoms of sub-micron sized holes of high aspect ratios. The sputtering is made possible by provision for a supplemental RF plasma generating source by which RF energy is reactively coupled into the gas within the chamber in close proximity to the surface of a sputtering target, preferably adjacent the periphery thereof. The pressure in the chamber as well as the power to an RF electrode by which the supplemental plasma is energized and the DC power by which the main target is energized are dynamically controlled so that the plasma is sustained at low pressure. First, the pressure in the chamber is raised to above 1 mTorr while the RF power on the supplemental electrode is applied to ignite the plasma, then this RF power is reduced and DC power on the target is increased to an operating level, whereupon the pressure in the chamber is reduced to below 1 mTorr for the low pressure sputtering of the wafer.

Method and apparatus for low pressure sputtering

An ionized physical vapor deposition apparatus is provided with a helical RF coil that surrounds the chamber wall opposite a space between a target and a substrate holder. The coil is behind a quartz window in the wall of the chamber, which protects the coil from adverse interaction with plasma. The coil is energized with RF energy, preferably in the 0.1 to 60 MHz range, to form a secondary plasma in a volume of the space between the substrate holder and the main plasma that is adjacent the target. A shield between the space and the dielectric material prevents coating from forming on the window. The shield is formed of a plurality of angled sections that are spaced to facilitate communication of a secondary RF plasma from adjacent the window to the volume of the chamber where the sputtered material is ionized, with the sections angled and spaced to shadow at least most of the target from the window. In one embodiment, a plurality of axially spaced frusto-conical sections are used, with axial gaps to interrupt current eddy paths around the chamber. In another embodiment, the sections are in the form of a plurality angled axially extending circumferentially spaced blades. The shields may be commonly or separately biased to control contamination and to optimize the uniformity of coating on the substrate and the directionality of the flux of ionized material at the substrate.

Apparatus for ionized sputtering

A plasma processing system for sputter etching a substrate with reduced particle contamination comprises a plasma processing chamber having an interior surface which defines a processing space containing a substrate. An electrical element couples electrical energy into a portion of the processing space to generate a plasma therein for etching the substrate. A heating device is coupled to the reactor and is operable for controllably heating the processing chamber interior surface to a selected temperature. The heating device is controlled by a temperature control circuit which turns the heating device to an ON state and operates the heating device to heat the processing chamber to a selected temperature when the electrical element is not coupling energy to the processing chamber and the plasma is extinguished. The selected temperature achieved by the heating device is related to the temperature of the processing chamber during plasma generation such that the interior surface is maintained at a relatively constant temperature before, during and after processing to prevent flaking of sputter material from the interior surface and generation of contamination particles within the processing space.

Plasma sputter etching system with reduced particle contamination

A plasma noise and arcing suppressor apparatus and method includes a suppressor circuit electrically coupled between a DC power supply and a sputter target inside of a deposition chamber. The suppressor circuit includes an inductive element electrically connected in parallel with a rectifying element. An anode of the rectifying element is coupled to the negative output terminal of the DC power supply such that during a random fluctuation in sputtering current level at the output of the power supply, attributable to random electrical noise and arcing conditions in the sputtering plasma inside the chamber, the rectifying element is negatively biased and is generally non-conductive and the inductive element stores current energy from the sputtering current level fluctuation. Subsequently, the rectifying element is momentarily positively biased and current flows in a current loop through the inductive element and rectifying element to dissipate the stored energy in the suppressor circuit and thereby reduce the amount of energy from the random fluctuation which is conducted through the plasma to thereby reduce the noise and arcing within the plasma. A limiting resistor may be placed in series with the rectifying element to limit the current flowing through the rectifying element and to further dissipate the stored energy in the suppressor circuit.

Plasma noise and arcing suppressor apparatus and method for sputter

The plasma processing system comprises a processing chamber with a processing space therein to contain a substrate. An electrical element is operable to couple electrical energy into the processing space to generate a plasma and is further operable to interrupt the power to the processing space to extinguish the plasma upon completion of the processing. An electrode positioned inside the chamber is electrically coupled to the substrate and to a DC bias power supply which selectively supplies DC power to the electrode to bias the substrate. A DC bias control circuit coupled to the power supply selectively controls the biasing of the substrate and is operable to briefly supply DC power to the electrode and the substrate proximate the time when the power to the generated plasma is interrupted to momentarily DC bias the substrate such that, as the plasma is extinguished, charged contaminants particles suspended within the plasma are repelled away from the biased substrate to prevent contamination of the substrate.

Plasma processing system with reduced particle contamination

A shade is disposed on the inner wall of an inductively coupled plasma chamber, covering a protected zone of the wall generally opposite to the inductive coil driving the chamber, preventing accumulation of material sputtered from a wafer in this zone, and thus restricting closed paths for eddy current flow along the chamber wall, improving inductive coupling of electrical power to the plasma in the chamber.

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Middletown, NY, United States of America

Alexander D Lantsman