Abstract: An oxide etching process, particular useful for selectively etching oxide over a feature having a non-oxide composition, such as silicon nitride and especially when that feature has a corner that is prone to faceting during the oxide etch. The invention preferably uses the unsaturated 4-carbon fluorocarbons, specifically hexafluorobutadiene (C4F6), which has a below 10°C. and is commercially available. The hexafluorobutadiene together with argon is excited into a high-density plasma in a reactor which inductively couples plasma source power into the chamber and RF biases the pedestal electrode supporting the wafer. Preferably, a two-step etch is used process is used in which the above etching gas is used in the main step to provide a good vertical profile and a more strongly polymerizing fluorocarbon such as difluoromethane (CH2F2) is added in the over etch to protect the nitride corner.

Abstract: An oxide etching process, particularly useful for selectively etching oxide over a feature having a non-oxide composition, such as silicon nitride and especially when that feature has a corner that is prone to faceting during the oxide etch. One aspect of the invention uses one of four hydrogen-free fluorocarbons having a low F/C ratio, specifically hexafluorobutadiene (C4F6), octafluoropentadiene (C5F8), hexafluorocyclobutene (C4F6), and hexafluorobenzene (C6F6). At least hexafluorobutadiene has a boiling point below 10° C. and is commercially available. Another aspect of the invention, uses an unsaturated fluorocarbon such as pentafluoropropylene (C3HF5), and trifluoropropyne (C3HF3), both of which have boiling points below 10° C. and are commercially available.

Abstract: A plasma etching process, particularly useful for selectively etching oxide over a feature having a non-oxide composition, such as silicon nitride and especially when that feature has a corner that is prone to faceting during the oxide etch. A primary fluorine-containing gas, preferably hexafluorobutadiene (C4F6), is combined with a significantly larger amount of the diluent gas xenon (Xe) to enhance nitride selectivity without the occurrence of etch stop. The chemistry is also useful for etching oxides in a time oxide etch in which holes and corners have already been formed, for example counterbore vias in a dual damascene structure. In this case, the relative amount of xenon need not be so high, but xenon still reduces faceting of the oxide corners. The invention may be used with related heavy fluorocarbons and other fluorine-based etching gases.

Abstract: There is disclosed a plasma reactor for processing a semiconductor workpiece such as a wafer, including a chamber having an overhead ceiling with a three-dimensional shape such as a hemisphere or dome. The reactor further includes an inductive antenna over the ceiling which may be conformal or nonconformal in shape with the ceiling. The ceiling may be a semiconductor material so that it can function as both a window for the inductive field of the antenna as well as an electrode which can be grounded, or to which RF power may be applied or which may be allowed to float electrically. The reactor includes various features which allow the radial distribution of the plasma ion density across the wafer surface to be adjusted to an optimum distribution for processing uniformity across the wafer surface.

Abstract: An oxide etching recipe including a heavy hydrogen-free fluorocarbon having F/C ratios less than 2, preferably C4F6, an oxygen-containing gas such as O2 or CO, a lighter fluorocarbon or hydrofluorocarbon, and a noble diluent gas such as Ar or Xe. The amounts of the first three gases are chosen such that the ratio (F—H)/(C—O) is at least 1.5 and no more than 2. Alternatively, the gas mixture may include the heavy fluorocarbon, carbon tetrafluoride, and the diluent with the ratio of the first two chosen such the ratio F/C is between 1.5 and 2.

Abstract: A plasma etching process, particularly useful for selectively etching oxide over a feature having a non-oxide composition, such as silicon nitride and especially when that feature has a comer that is prone to faceting during the oxide etch. A primary fluorine- containing gas, preferably hexafluorobutadiene (C4F6), is combined with a significantly larger amount of the diluent gas xenon (Xe) enhance nitride selectivity without the occurrence of etch stop. The chemistry is also useful for etching oxides in which holes and comers have already been formed, for which the use of xenon also reduces faceting of the oxide. For this use, the relative amount of xenon need not be so high. The invention may be used with related heavy fluorocarbons and other fluorine-based etching gases.

Abstract: A substrate cleaning method comprises exposing a substrate 30 to an energized process gas to remove residue 60 and resist material 50 from the substrate 30. In one version, the process gas comprises cleaning gas, such as an oxygen-containing gas, and an additive gas, such as NH3. In one version, the process gas is introduced to remove residue 60 and resist material 50 from the substrate and to remove residue from surfaces in the process chamber 75.

Abstract: An integrated self aligned contact process includes oxide etch with high oxide etch rate, integrated selective oxide etch and nitride liner removal with high selectivity to corner nitride with the ability to remove the bottom nitride liner, and stripping of all polymer and photoresist. C4F8 and CH2F2 are used for the high selectivity oxide etch step. The unique behavior of CH2F2 in high density plasma allows polymer protection to form on the nitride corner/sidewall while at the same time etching the bottom nitride.

Abstract: The invention is embodied in a method of processing a semiconductor workpiece in a plasma reactor chamber, including supplying a polymer and etchant precursor gas containing at least carbon and fluorine into the chamber at a first flow rate sufficient of itself to maintain a gas pressure in the chamber in a low pressure range below about 20 mT, supplying a relatively non-reactive gas into the chamber at second flow rate sufficient about one half or more of the total gas flow rate into the chamber, in combination with the first flow rate of the precursor gas, to maintain the gas pressure in the chamber in a high pressure range above 20 mT, and applying plasma source power into the chamber to form a high ion density plasma having an ion density in excess of 1010 ions per cubic centimeter.

Abstract: The invention is embodied by a plasma reactor for processing a workpiece, including a reactor enclosure defining a processing chamber, a semiconductor ceiling window, a base within the chamber for supporting the workpiece during processing thereof, the semiconductor ceiling including a gas inlet system for admitting a plasma precursor gas into the chamber through the ceiling, and apparatus for coupling plasma source power into the chamber.

Abstract: An oxide etching process, particular useful for selectively etching oxide over a feature having a non-oxide composition, such as silicon nitride and especially when that feature has a corner that is prone to faceting during the oxide etch. The invention uses one of three unsaturated 3- and 4-carbon fluorocarbons, specifically hexafluorobutadiene (C4F6), pentafluoropropylene (C3HF5), and trifluoropropyne (C3HF3), all of which have boiling points below 10° C. and are commercially available. The unsaturated hydrofluorocarbon together with argon is excited into a high-density plasma in a reactor which inductively couples plasma source power into the chamber and RF biases the pedestal electrode supporting the wafer. Preferably, a two-step etch is used process is used in which the above etching gas is used in the main step to provide a good vertical profile and a more strongly polymerizing fluorocarbon such as difluoromethane (CH2F2) is added in the over etch to protect the nitride corner.

Abstract: The invention is embodied by a plasma reactor for processing a workpiece, including a reactor enclosure defining a processing chamber, a semiconductor window, a base within the chamber for supporting the workpiece during processing thereof, a gas inlet system for admitting a plasma precursor gas into the chamber, and an inductive antenna adjacent a side of the semiconductor window opposite the base for coupling power into the interior of the chamber through the semiconductor window electrode.

Abstract: There is disclosed a plasma reactor for processing a semiconductor workpiece such as a wafer, including a chamber having an overhead ceiling with a three-dimensional shape such as a hemisphere or dome. The reactor further includes an inductive antenna over the ceiling which may be conformal or nonconformal in shape with the ceiling. The ceiling may be a semiconductor material so that it can function as both a window for the inductive field of the antenna as well as an electrode which can be grounded, or to which RF power may be applied or which may be allowed to float electrically. The reactor includes various features which allow the radial distribution of the plasma ion density across the wafer surface to be adjusted to an optimum distribution for processing uniformity across the wafer surface.

Abstract: The invention is embodied by a plasma reactor for processing a workpiece, including a reactor enclosure defining a processing chamber, a semiconductor ceiling window, a base within the chamber for supporting the workpiece during processing thereof, the semiconductor ceiling including a gas inlet system for admitting a plasma precursor gas into the chamber through the ceiling, and apparatus for coupling plasma source power into the chamber.

Abstract: An oxide etch process that is highly selective to nitride, thereby being beneficial for a self-aligned contact etch of silicon dioxide to an underlying thin layer of silicon nitride. The process uses difluoromethane (CH.sub.2 F.sub.2) for its strong polymer forming and a greater amount of trifluoromethane (CHF.sub.3) for its strong etching, and with a high diluent fraction of argon (Ar). The etch process is performed at a low pressure of about 20 milliTorr in a high-density plasma etching chamber.