Patent JPS5487172A successfully refreshed from Google Patents.
← Back to Patent Explorer
JPS5487172A Expired / Lapsed JP ⏱️ 0.0 years remaining

Manufacture for simiconductor device

Assignee: Hitachi Ltd
•
Filing: 1977-12-23
•
Granted: —
•
Expires: 1997-12-23
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract PURPOSE: To provide the opening smooth for the shoulder and good in the machining accuracy, by immersing the protective film of substrate into etching solution, after drying etching on the way of thickness from the surface for the substrate protection film. CONSTITUTION: The resist mask 4 is overlaid on the surface protection film SiO 2 3, and the film 3 is plasma-etched on the way of thickness of the film 3, remaining SiO 2 by about 0.1 μ at the bottom of the hole 7. Next, the remaining film is etched by immersing it in NH 4 F solution, forming the hole 8. At this time, the SiO 2 3 is opened with smooth shape with side etching even for the surface in contact with the resist mask 4. The mask is removed and the Al electrode 9 is provided. Since the shoulder of the hole 8 is smooth, no open wire is caused, and further, the remaining SiO 2 film is thin, the accuracy of size of the hole 8 is very excellently formed with wet etching. COPYRIGHT: (C)1979,JPO&Japio

Inventors

  • 👤 Ryoichi Fukuyama

Bibliographic Details

Application Number —
Jurisdiction JP
Data Source google_patents
Last Synchronized 2026-11-05 18:17
CPC Classifications
H; H10; H10D; H10D8/00; H10D8/01

Claims Analysis

Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Maintenance schedule is calculated for granted US utility patents.

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag