Abstract: Apparatus for plasma etching a layer of material upon a substrate comprising an anode having a first region protruding from a second region, wherein the second region defines a plane and the first region extends from said plane. In one embodiment, at least one solenoid is disposed near the apparatus to magnetize the plasma.

Abstract: A capacitively coupled reactor for plasma etch processing of substrates at subatmospheric pressures includes a chamber body defining a processing volume, a lid provided upon the chamber body, the lid being a first electrode, a substrate support provided in the processing volume and comprising a second electrode, a radio frequency source coupled at least to one of the first and second electrodes, a process gas inlet configured to deliver process gas into the processing volume, and an evacuation pump system having pumping capacity of at least 1600 liters/minute. The greater pumping capacity controls residency time of the process gases so as to regulate the degree of dissociation into more reactive species.

Abstract: A plasma reactor for processing a semiconductor wafer having a wafer diameter within a vacuum chamber of the reactor has a wafer support pedestal in the vacuum chamber extending upwardly from a floor of the vacuum chamber. The wafer support pedestal includes a top layer having a generally planar surface for supporting the wafer, the top layer having a diameter on the order of the wafer diameter. A conductive base underlies and supports the top layer, the conductive base having a diameter at least as great as the wafer diameter. An RF power output terminal below the floor of the vacuum chamber transmits power through an elongate inner conductor within and generally parallel to an axis of the wafer support pedestal, the elongate inner conductor having a bottom end connected to the RF power output terminal and a top end terminated at the conductive base.

Abstract: A ring or collar surrounding a semiconductor workpiece in a plasma chamber. According to one aspect, the ring has an elevated collar portion having an inner surface oriented at an obtuse angle to the plane of the workpiece, this angle preferably being 135°. This angular orientation causes ions bombarding the inner surface of the elevated collar to scatter in a direction more parallel to the plane of the workpiece, thereby reducing erosion of any dielectric shield at the perimeter of the workpiece, and ameliorating spatial non-uniformity in the plasma process due to any excess ion density near such perimeter. In a second aspect, the workpiece is surrounded by a dielectric shield, and the shield is covered by a non-dielectric ring which protects the dielectric shield from reaction with, or erosion by, the process gases.

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: An oxide etch process practiced in a plasma etch reactor, such as a magnetically enhanced reactive ion etch (MERIE) reactor. The etching gas includes approximately equal amounts of a hydrogen-free fluorocarbon, most preferably C4F6, and oxygen and a much larger amount of argon diluent gas. The magnetic field is preferably maintained above about 50 gauss and the pressure at 40 milliTorr or above with chamber residence times of less than 70 milliseconds. A two-step process may be used for etching holes with very high aspect ratios. In the second step, the magnetic filed and the oxygen flow are reduced. Other fluorocarbons may be substituted which have F/C ratios of less than 2 and more preferably no more than 1.6 or 1.5.

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 magnetic field generator for producing a magnetic field that accelerates plasma formation is placed proximate a reaction chamber of semiconductor substrate processing system. The magnetic field generator has four main magnetic coil sections for producing a magnetic field nearly parallel to the top surface of a support pedestal in the reaction chamber and four sub-magnetic coil sections placed generally coaxially with the main magnetic coil sections to produce a magnetic field of the direction opposite of that of the magnetic field produced with the main magnetic coil sections. In the magnetic field generator, magnetic fields of opposite polarities are superimposed on each other when electric currents of opposite directions are applied to the main and sub-magnetic coil sections.

Abstract: A capacitively coupled reactor for plasma etch processing of substrates at subatmospheric pressures includes a chamber body defining a processing volume, a lid provided upon the chamber body, the lid being a first electrode, a substrate support provided in the processing volume and comprising a second electrode, a radio frequency source coupled at least to one of the first and second electrodes, a process gas inlet configured to deliver process gas into the processing volume, and an evacuation pump system having pumping capacity of at least 1600 liters/minute. The greater pumping capacity controls residency time of the process gases so as to regulate the degree of dissociation into more reactive species.

Abstract: A capacitively coupled reactor for plasma etch processing of substrates at subatmospheric pressures includes a chamber body defining a processing volume, a lid provided upon the chamber body, the lid being a first electrode, a substrate support provided in the processing volume and comprising a second electrode, a radio frequency source coupled at least to one of the first and second electrodes, a process gas inlet configured to deliver process gas into the processing volume, and an evacuation pump system having pumping capacity of at least 1600 liters/minute. The greater pumping capacity controls residency time of the process gases so as to regulate the degree of dissociation into more reactive species.

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: A method and apparatus for controlling a magnetic field gradient within a magnetically enhanced plasma reactor. The apparatus comprises a cathode pedestal supporting a wafer within an enclosure, a plurality of electromagnets positioned proximate the enclosure for producing a magnetic field in the enclosure and a magnetic field control element, positioned proximate the electromagnets, for controlling the magnetic field proximate a specific region of the wafer.

Abstract: An oxide etch process practiced in a plasma etch reactor, such as a magnetically enhanced reactive ion etch (MERIE) reactor. The etching gas includes approximately equal amounts of a hydrogen-free fluorocarbon, most preferably C4F6, and oxygen and a much larger amount of argon diluent gas. The magnetic field is preferably maintained above about 50 gauss and the pressure at 40 milliTorr or above with chamber residence times of less than 70 milliseconds. A two-step process may be used for etching holes with very high aspect ratios. In the second step, the magnetic filed and the oxygen flow are reduced. Other fluorocarbons may be substituted which have F/C ratios of less than 2 and more preferably no more than 1.6 or 1.5.

Abstract: An oxide etch process practiced in magnetically enhanced reactive ion etch (MERIE) plasma reactor. The etching gas includes approximately equal amounts of a hydrogen-free fluorocarbon, most preferably C4F6, and oxygen and a much larger amount of argon diluent gas. The magnetic field is preferably maintained above about 50 gauss and the pressure at 40 milliTorr or above with chamber residence times of less than 70 milliseconds. A two-step process may be used for etching holes with very high aspect ratios. In the second step, the magnetic filed and the oxygen flow are reduced. Other fluorocarbons may be substituted which have F/C ratios of less than 2 and more preferably no more than 1.6 or 1.5.

Abstract: A method for etching a dielectric in a thermally controlled plasma etch chamber with an expanded processing window. The method is adapted to incorporate benefits of a the thermal control and high evacuation capability of the chamber. Etchent gases include hydrocarbons, oxygen and inert gas. Explanation is provided for enablling the use of hexafluoro-1,3-butadiene in a capacitively coupled etch plasma. The method is very useful for creating via, self aligned contacts, dual damascene, and other dielectric etch.

Abstract: A ring or collar surrounding a semiconductor workpiece in a plasma chamber. According to one aspect, the ring has an elevated collar portion having an inner surface oriented at an obtuse angle to the plane of the workpiece, this angle preferably being 135°. This angular orientation causes ions bombarding the inner surface of the elevated collar to scatter in a direction more parallel to the plane of the workpiece, thereby reducing erosion of any dielectric shield at the perimeter of the workpiece, and ameliorating spatial non-uniformity in the plasma process due to any excess ion density near such perimeter. In a second aspect, the workpiece is surrounded by a dielectric shield, and the shield is covered by a non-dielectric ring which protects the dielectric shield from reaction with, or erosion by, the process gases.

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 plasma pretreatment performed prior to a plasma oxide etch. The plasma pretreatment is performed with an argon plasma or a carbon tetrafluoride and trifluoromethane plasma with lower power than in the main etch or is performed with a plasma of difluoromethane or trifluoromethane and carbon monoxide but no argon diluent gas. Thereby, striations on the oxide wall are reduced.

Abstract: A ring or collar surrounding a semiconductor workpiece in a plasma chamber. According to one aspect, the ring has an elevated collar portion having an inner surface oriented at an obtuse angle to the plane of the workpiece, this angle preferably being 135°. This angular orientation causes ions bombarding the inner surface of the elevated collar to scatter in a direction more parallel to the plane of the workpiece, thereby reducing erosion of any dielectric shield at the perimeter of the workpiece, and ameliorating spatial non-uniformity in the plasma process due to any excess ion density near such perimeter. In a second aspect, the workpiece is surrounded by a dielectric shield, and the shield is covered by a non-dielectric ring which protects the dielectric shield from reaction with, or erosion by, the process gases.

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.