×

Method for forming a semiconductor device having a floating gate

  • US 5,702,964 A
  • Filed: 10/17/1995
  • Issued: 12/30/1997
  • Est. Priority Date: 10/17/1995
  • Status: Expired due to Term
First Claim
Patent Images

1. A method for forming of a semiconductor device including a transistor having a floating gate, comprising the steps of:

  • (a) forming a first insulating layer and a first conductive layer on a surface of the substrate;

    (b) patterning the first conductive layer on a cell forming area for forming preliminary floating gate electrodes spaced by a distance and implanting ions on the cell forming area;

    (c) forming a second insulating layer on the resulting surface formed after step (b) and etching the second insulating layer so that the second insulating layer remains on a side wall of the preliminary floating gate electrodes and fills the distance between preliminary floating gate electrodes;

    (d) forming a third insulating layer on the resulting surface formed after step (c);

    (e) forming a second conductive layer on the third insulating layer;

    (f) forming a fourth insulating layer on the second conductive layer;

    (g) forming gate electrode patterns by patterning the fourth insulating layer and the second conductive layer, wherein the gate electrode patterns have a first distance between the gate patterns in a portion to be a contact hole, and a second distance between the gate patterns is arranged in another portion, the first distance being wider than the second distance;

    (h) forming a floating gate electrode by patterning the third insulating layer and the preliminary floating gate electrodes using the gate electrode patterns as a mask;

    (i) forming source and drain regions by ion implantation;

    (j) forming a fifth insulating layer and anisotropically etching the fifth insulating layer for forming a contact hole; and

    (k) filling the contact hole with a third conductive layer, and patterning the third conductive layer into wiring.

View all claims
  • 6 Assignments
Timeline View
Assignment View
    ×
    ×