Semiconductor device having an improved packing density and high reliability

#1. Field of the Invention

#The present invention relates to a semiconductor device in which there is formed a contact hole in a manner resulting in a structure having an improved packing density and high reliability.

#2. Description of the Prior Art

#The above objects and other advantages of the present invention will become more apparent by describing in detail a preferred embodiment of the present invention with reference to the attached drawings in which:

#FIG. 1A illustrates a layout of a semiconductor device which shows a conventional method for forming a contact hole in a semiconductor device;

#FIG. 1B is a cross section of the semiconductor device of FIG. 1A cut along line 1B--1B;

#In the following figures now to be explained in greater detail, like reference numerals as those in FIGS. 1A and 1B are used to represent like components.

#FIG. 2A shows a layout where mask patterns P2 forming contact holes are not located along a shortest line distance across a field oxide layer. L.sub.12 represents a shortest distance between contact holes, L.sub.10 represents the shortest distance from the contact hole (field oxide layer side) to the edge of the field oxide layer, and .theta. represents the angle between a shortest horizontal line distance connecting contact holes and a shortest distance across the field oxide layer.

#In FIG. 2A, because shortest distance L between contact holes is lengthened by ##EQU1## compared with the shortest distance L.sub.11 of FIG. 1A, L.sub.s is increased proportionally.