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: The invention is embodied in an RF plasma reactor for processing a semiconductor wafer, including as reactor chamber bounded by a chamber wall defining an interior region of the chamber, a gas inlet, an RF power source and an RF power applicator proximal the chamber and connected to the RF power source, and an opening in this chamber communicating with the interior region of the chamber. The invention further includes a magnet apparatus disposed adjacent said opening to resist flow of plasma ions through the opening, and the magnet apparatus comprising a first pair of magnetic poles and a second pair of magnetic poles, the first pair of magnetic poles facing the second pair of magnetic poles across the opening.

Abstract: The invention is embodied in a plasma reactor including a chamber enclosure having a process gas inlet and including a ceiling, a sidewall and a workpiece support pedestal capable of supporting a workpiece at a plasma processing location facing the ceiling, the workpiece processing location and ceiling defining a process region therebetween, the pedestal being spaced from said sidewall to define a pumping annulus therebetween having inner and outer walls, to permit process gas to be evacuated therethrough from the process region. The invention further includes a pair of opposing plasma confinement magnetic poles arranged adjacent the annulus within one of the inner and outer walls of the annulus, the opposing magnetic poles being axially displaced from one another the opposite poles being oriented to provide maximum magnetic flux in a direction across the annulus and a magnetic flux at the processing location less than the magnetic flux across the annulus.

Abstract: A plasma etch process, particularly applicable to an self-aligned contact etch in a high-density plasma for selectively etching oxide over nitride, although selectivity to silicon is also achieved. In the process, a fluoropropane or a fluoropropylene is a principal etching gas in the presence of a substantial amount of an inactive gas such as argon. Good nitride selectivity has been achieved with hexafluoropropylene (C3F6), octafluoropropane (C3F8), heptafluoropropane (C3HF7), hexafluoropropane (C3H2F6). The process may use one or more of the these gases in proportions to optimize selectivity and a wide process window. Difluoromethane (CH2F2) or other fluorocarbons may be combined with the above gases, particularly with C3F6 for optimum selectivity over other materials without the occurrence of etch stop in narrow contact holes and with a wide process window.

Abstract: A plasma reactor appropriate for fabrication, especially etching, of semiconductor integrated circuits and similar processes in which the chamber has a top comprising a truncated conical dome and, preferably, a counter electrode disposed at the top of the conical dome. An RF coil is wrapped around the conical dome to inductively couple RF energy into a plasma within the chamber dome. The dome temperature can be controlled in a number of ways. A heat sink can be attached to the outside rim of the dome. A rigid conical thermal control sheath can be fit to the outside of the dome, and any differential thermal expansion between the two is accommodated by the conical geometry, thus assuring good thermal contact. The rigid thermal control sheath can include resistive heating, fluid cooling, or both. Alternatively, a flexible resistive heater can be wrapped around the dome inside the RF coil.

Abstract: The invention is embodied in a plasma reactor including a chamber enclosure having a process gas inlet and including a ceiling, a sidewall and a workpiece support pedestal capable of supporting a workpiece at a plasma processing location facing the ceiling, the workpiece processing location and ceiling defining a process region therebetween, the pedestal being spaced from said sidewall to define a pumping annulus therebetween having inner and outer walls, to permit process gas to be evacuated therethrough from the process region. The invention further includes a pair of opposing plasma confinement magnetic poles arranged adjacent the annulus within one of the inner and outer walls of the annulus, the opposing magnetic poles being axially displaced from one another the opposite poles being oriented to provide maximum magnetic flux in a direction across the annulus and a magnetic flux at the processing location less than the magnetic flux across the annulus.

Abstract: A plasma etch process, particularly applicable to a self-aligned contact etch or other advanced structures requiring high-selectivity to nitride or other non-oxide materials and producing no etch stop. The process is preferably performed in a high-density plasma reactor for etching holes with either high or low aspect rations. In this process, hexafluoropropylene (C3F6) is the principal etching gas and another hydrofluorocarbon such as CH2F2 or C3H2F6 is added at least in part for its polymer-forming ability, which increases selectivity of etching oxide to nitride. The process gas also includes a substantial amount of an inactive gas such as argon. The process gas mixture can be balanced between the active etching gas and the polymer former in proportions to optimize selectivity over other materials without the occurrence of etch stop in narrow contact holes and with a wide process window.

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: A plasma etch process, particularly applicable to a self-aligned contact etch or other advanced structures requiring high-selectivity to nitride or other non-oxide materials and no etch stop. The process is preferably performed in a high-density plasma reactor for etching holes with either high or low aspect rations. In this process, hexafluoropropane (C.sub.3 H.sub.2 F.sub.6) is the principal etching gas in the presence of a substantial amount of an inactive gas such as argon. The process can also be used with the closely related gases heptafluoropropane (C.sub.3 HF.sub.7) and pentafluoropropane (C.sub.3 H.sub.3 F.sub.5). The process may use one or more of the these gases in proportions to optimize selectivity over other materials without the occurrence of etch stop in narrow contact holes and with a wide process window. Difluoromethane (CH.sub.2 F.sub.2) or other fluorocarbons may be combined with the above gases for optimum selectivity for a design of a specific contact feature.

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.

Abstract: A composite silicon carbide article and its method of making in which a surface layer or film of silicon carbide is deposited, for example by chemical vapor deposition (CVD), over a free standing silicon carbide substrate, as is formed by bulk methods such as sintering and hot pressing. The article is advantageously used in a plasma reactor, especially an oxide etcher for semiconductor fabrication, and may be any of several parts including the chamber wall, chamber roof, or collar around the wafer. The bulk SiC provides an inexpensive and strong support structure of perhaps a complex shape while the CVD SiC film has advantages for plasma processing and may be tailored to particular uses. The composite SiC structure is particularly useful in that the electrical conductivities of the bulk SiC and film SiC may be separately controlled so as to provide, among many possibilities, a grounding plane, a window for RF electromagnetic radiation, or both.

Abstract: In accordance with the present invention, the plasma dry cleaning rate of semiconductor process chamber walls can be improved by placing a non-gaseous dry cleaning enhancement material in the position which was occupied by the workpiece during semiconductor processing. The non-gaseous dry cleaning enhancement material is either capable of generating dry cleaning reactive species and/or of reducing the consumption of the dry cleaning reactive species generated from the plasma gas feed to the process chamber.When process chamber non-volatile contaminant deposits are removed from plasma process chamber surfaces during plasma dry cleaning by placing a non-gaseous source of reactive-species-generating material within the plasma process chamber, the non-gaseous source of reactive-species-generating material need not be loacted upon or adjacent the workpiece support platform: however, this location provides excellent cleaning results in typical process chamber designs.

Abstract: In accordance with the present invention, the plasma dry cleaning rate of semiconductor process chamber walls can be improved by placing a non-gaseous dry cleaning enhancement material in the position which was occupied by the workpiece during semiconductor processing. The non-gaseous dry cleaning enhancement material is either capable of generating dry cleaning reactive species and/or of reducing the consumption of the dry cleaning reactive species generated from the plasma gas feed to the process chamber. When process chamber non-volatile contaminant deposits are removed from plasma process chamber surfaces during plasma dry cleaning by placing a non-gaseous source of reactive-species-generating material within the plasma process chamber, the non-gaseous source of reactive-species-generating material need not be loacted upon or adjacent the workpiece support platform: however, this location provides excellent cleaning results in typical process chamber designs.

Abstract: The plasma dry cleaning rate of semiconductor process chamber walls can be improved by placing a non-gaseous dry cleaning enhancement material in the position which was occupied by the workpiece during semiconductor processing. The non-gaseous dry cleaning enhancement material is either capable generating dry cleaning reactive species and/or of reducing the consumption of the dry cleaning reactive species generated from the plasma gas feed to the process chamber.When process chamber non-volatile contaminant deposits are removed from plasma process chamber surfaces during plasma dry cleaning by placing a non-gaseous source of reactive-species-generating material within the plasma process chamber, the non-gaseous source of reactive-species-generating material need not be located upon or adjacent the workpiece support platform: however, this location provides excellent cleaning results in typical process chamber designs.

Abstract: A method and apparatus for generating a medium density plasma in a reactive ion etching chamber. A conventional reactive ion etching technique, using multiple electrodes for capacitive coupling of power into the chamber to establish and sustain a plasma, is combined with inductive coupling for plasma enhancement only. A first source of high frequency power is coupled to at least one of the electrodes to generate the plasma under conditions similar to those used in a conventional reactive ion etching system, and a second source of high frequency power is coupled to an inductive coil surrounding the plasma, to enhance the plasma density without adversely affecting wafers being processed in the chamber.

Abstract: A reactive ion etching or magnetically enhanced reactive ion etching system consists of a cathode support structure, a shield structure disposed around the cathode, an insulator disposed between the cathode and the shield structure, and a clamping ring capable of mating with the top edge of the insulator. The insulator has a generally cylindrical shape with a flange that extends outward between the shield structure and the clamping ring. A gap between the clamping ring and the top edge of the insulator is controlled to 20 thousandths of an inch or less to restrict an RF coupling path between the shield and the cathode. In addition, the flange acts to interrupt the plasma conduction path between the shield structure and the cathode. By inhibiting plasma conduction between the shield and the cathode, reactive ion etching systems in accordance with the present invention operate in a higher pressure, higher power regime without arcing or exciting a secondary plasma.

Abstract: An ion energy analyzer having a micro-channel plate where the geometric filtering characteristics of the micro-channel plate are electrically controlled. The ion energy analyzer contains a metallic collector, a control grid and a micro-channel plate, all formed into a cylindrical stack where the collector, control grid and micro-channel plate are separated by ceramic insulating washers. A control element is formed within each aperture of the micro-channel plate for controlling a critical angle of each aperture. A voltage is applied to the control element such that an electric field is generated within each micro-channel. By varying the magnitude of the electric field, the critical angle of the micro-channel plate can be electrically controlled, and as such, certain ion trajectories can be selected for entry into the ion energy analyzer.

Abstract: A domed plasma reactor chamber uses an antenna driven by RF energy (LF, MF, or VHF) which is inductively coupled inside the reactor dome. The antenna generates a high density, low energy plasma inside the chamber for etching metals, dielectrics and semiconductor materials. Auxiliary RF bias energy applied to the wafer support cathode controls the cathode sheath voltage and controls the ion energy independent of density. Various magnetic and voltage processing enhancement techniques are disclosed, along with etch processes, deposition processes and combined etch/deposition processed. The disclosed invention provides processing of sensitive devices without damage and without microloading, thus providing increased yields.

Abstract: Capacitive coupling and RF power dissipation is advantageously reduced in the present invention by employing an RF coil having plural coil sections, each coil section connected across an RF source, commonly tapped ones of the coil sections being wound in opposite directions. Capacitive coupling and RF power dissipation is further reduced by employing a top lid having an outer insulating annulus and an inner conducting disk portion, the conducting disk portion being displaced or spaced apart from the coil by the width of the annulus. This displacement significantly reduces the RF power dissipation or coupling from the top winding of the coil to the lid. Furthermore, the plural coil sections or mirror coil configuration reduces sputtering of insulative material induced by capacitive RF coupling.