Patent · US Expired

Method of manufacturing high capacity semiconductor capacitance devices

US4507159A · kind A · utility

20Cited by
3References
25Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 7, 1981
Grant dateMar 26, 1985
Priority date
Expiry dateOct 7, 2001

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D1/64

Abstract

The present invention provides for a method for manufacturing a charge storage region in a semiconductor substrate for a memory cell in a dynamic RAM, comprising forming an insulating layer on the substrate, forming a masking layer over the insulating layer, forming at least one aperture in the masking layer, the aperture defining the charge storage region in the semiconductor substrate, implanting dopant ions of a first polarity through the aperture for diffusion through the substrate, and implanting dopant ions of a second polarity through the aperture for diffusion through the substrate to a lesser degree than the first polarity dopant diffusion so that the diffusion of the first polarity dopant with respect to the diffusion of the second polarity dopant forms a P-N junction substantially aligned with the edge of the masking layer aperture to define the periphery of the charge storage region. One way of diffusing the second polarity dopant to a lesser degree than the first polarity dopant in the substrate is to select a first polarity dopant which has a diffusivity greater than the second polarity dopant. Another way of achieving the desired diffusion of first polarity dopant wi…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.