Single-piece gas director for plasma reactors

{
  "publication_number": "US5942074A",
  "country": "US",
  "kind": "A",
  "title": "Single-piece gas director for plasma reactors",
  "abstract": "Plasma etching apparatus for use in the manufacture of integrated circuit devices utilizes a one-piece director at an input of a process chamber that includes a sleeve portion and a bell jar portion. The director directs incoming process gas in the sleeve portion radially before the gas flows past electrodes used to establish a radio frequency discharge that ionizes the process gas. The one-piece director is clamped between the cap and the sleeve portion of the process chamber to eliminate the need for screws.",
  "claims": [
    "1. Apparatus for plasma processing a workpiece comprising: a process chamber for housing the workpiece to be processed comprising at least a bell jar portion and a sleeve portion, the sleeve portion having side walls that define a passage for introducing a process gas into the bell jar portion; electrodes disposed along the sleeve portion for ionizing the process gas as it flows past; and a one-piece director for directing the gas radially towards the side walls of the sleeve portion before it flows past the electrodes.",
    "2. The apparatus of claim 1 in which the one-piece director comprises a first portion that is of a diameter larger than the inner diameter of the sleeve portion and that is supported on a top edge of the side walls of the sleeve portion, a second portion of diameter being slightly smaller than said inner diameter for a close fit inside the sleeve portion, and a third portion of a diameter smaller than that of the second portion for leaving an opening with the sleeve side walls, said third portion including a plurality of radial openings extending from a central opening that extends through said first and second portions.",
    "3. The apparatus of claim 1 in which the process chamber further comprises a load-lock base for housing a workpiece.",
    "4. The apparatus of claim 3 wherein the workpiece is a semiconductive wafer.",
    "5. The apparatus of claim 2 further comprising: cap means, which defines an opening therethrough, for flowing the process gas from a supply source into the opening of the sleeve portion; and the one-piece director means being located between the cap means and the sleeve portion with the opening in the cap means being aligned with the central opening in the one-piece director.",
    "6. A director for incorporation in a plasma processing apparatus that comprises a process chamber comprising at least a bell jar portion and a sleeve portion, the director comprising: a single integral piece comprising first, second, and third portions; the first portion being of a diameter larger than the inner diameter of the sleeve portion; the second portion being of a diameter smaller than said inner diameter so as to facilitate a close fit between the second portion and side walls of the sleeve portion; and the third portion being of a diameter smaller than that of the second portion, said third portion defining a plurality of radial openings therethrough extending from and intersecting with a central opening that extends through said first and second portions.",
    "7. Apparatus for plasma etching of a semiconductive wafer comprising: a process chamber for housing the semiconductive wafer to be etched comprising a sleeve portion, a bell jar portion, and load-lock base, the sleeve portion having side walls that define a passage therethrough for introducing an etching gas into the bell jar portion; electrodes disposed along the sleeve portion for ionizing the gas introduced into the sleeve; and one-piece director means, which is supported on a top edge of the side walls of the sleeve portion, for directing radially the process gas in the sleeve portion before it passes the electrodes for more uniform flow when it reaches a semiconductive wafer in the load-lock base.",
    "8. The apparatus of claim 7 further comprising cap means positioned over the director for introducing the process gas into the director.",
    "9. The apparatus of claim 7 in which the sleeve and bell jar portions, the load-lock base, and the director are of materials from a group including quartz and alumina.",
    "10. The apparatus of claim 8 in which the cap means is of anodized aluminum."
  ],
  "description_excerpt": "This invention relates to apparatus for using a plasma created in gaseous media in the manufacture of semiconductive integrated circuit devices, and more particularly, to their use in etching layers on semiconductive wafers in such manufacture.\n\nCurrently the use of plasma etching in the manufacture of integrated circuit devices is widespread. Typically the manufacture of integrated circuit devices involves the formation of multiple layers on the surface of a semiconductive wafer, typically of silicon. These layers need to be etched to desired patterns in accordance with desired device parameters. Typically, some of the etching needs to be anisotropic, for example in the creation of substantially vertical vias in the layers to provide conductive connections to particular regions of the semiconductive wafer, and some of the etching is preferably isotropic, for example in the planarization of surfaces of the layer-covered silicon wafer to facilitate the provision of the metalization layers used to provide interconnections between the components of the integrated circuit.\n\nBecause the apparatus used for such etching is expensive, it is generally important, for keeping costs adequately low, that the apparatus be capable of high throughput. To realize high throughput, it is important to keep the down-time of the apparatus short and its maintenance easy.",
  "cpc": [
    "H01J 37/32082",
    "H01J 37/3244"
  ],
  "ipc": [
    "H01J 37/32"
  ],
  "assignees": [
    "Lam Research Corp"
  ],
  "inventors": [
    "Eric Howard Lenz",
    "Keith Edward Dawson"
  ],
  "filing_date": "1996-03-29",
  "publication_date": "1999-08-24",
  "grant_date": "1999-08-24",
  "priority_date": "1996-03-29",
  "application_number": "US-62396796-A",
  "family_id": "24500070",
  "cited_by_count": 36,
  "citations": [
    "US4632624A"
  ]
}