Flash Memory Device Using Double Patterning Technology and Method of Manufacturing the Same

Abstract

Provided are a flash memory device and a method of manufacturing the same. The flash memory device includes strings. Each of the strings has a string selection line, a ground selection line, and an odd number of word lines formed between the string selection line and the ground selection line.

1 . A flash memory device having string, each of the strings comprising:
 a string selection line;   aground selection line; and   an odd number of word lines formed between the string selection line and the ground selection line.   
     
     
         2 . The flash memory device of  claim 1 , wherein the word lines each have a width greater than a distance between a pair of adjacent word lines. 
     
     
         3 . The flash memory device of  claim 1 , wherein one of the word lines is not involved in storage of information. 
     
     
         4 . The flash memory device of  claim 3 , wherein the word line that is not involved in the storage of information is formed adjacent to the ground selection line. 
     
     
         5 . The flash memory device of  claim 1 , wherein each of a distance between the string selection line and a word line adjacent to the string selection line and a distance between the ground selection line and a word line adjacent to the ground selection line is equal to a distance between a pair of adjacent word lines. 
     
     
         6 . The flash memory device of  claim 5 , wherein a distance between the string selection line and the ground selection line is equal to (the total number of word lines+½) multiplied by the distance of one pitch. 
     
     
         7 . The flash memory device of  claim 1 , wherein a distance between the string selection line and a word line adjacent to the string selection line is greater than a distance between a pair of adjacent word lines. 
     
     
         8 . The flash memory device of  claim 7 , wherein the distance between the string selection line and the word line adjacent to the string selection line is equal to two times the distance between a pair of adjacent word lines. 
     
     
         9 . The flash memory device of  claim 8 , wherein a distance between the string selection line and the ground selection line is equal to the (total number of word lines+1) multiplied by the distance of one pitch. 
     
     
         10 . The flash memory device of  claim 7 , wherein a distance between the ground selection line and a word line adjacent to the ground selection line is greater than the distance between a pair of adjacent word lines. 
     
     
         11 . The flash memory device of  claim 10 , wherein the distance between the ground selection line and the word line adjacent to the ground selection line is equal to two times the distance between a pair of adjacent word lines. 
     
     
         12 . The flash memory device of  claim 11 , wherein a distance between the string selection line and the ground selection line is equal to the (total number of word lines+0.5) multiplied by the distance of one pitch. 
     
     
         13 . The flash memory device of  claim 1 , wherein three of the word lines are not involved in storage of information. 
     
     
         14 . The flash memory device of  claim 13 , wherein, one of the three word lines that are not involved in the storage of information is formed adjacent to the string selection line, and two remaining word lines of the three word lines that are not involved in the storage of information are formed adjacent to the ground selection line. 
     
     
         15 . The flash memory device of  claim 1 , wherein the string selection line, the ground selection line and the word lines are each formed using double patterning technology. 
     
     
         16 . A flash memory device having strings, each of the strings comprising:
 a string selection line;   a ground selection line; and   an even number of word lines formed between the string selection line and the ground selection line;   wherein a distance between the string selection line and a word line adjacent to the string selection line is greater than a distance between a pair of adjacent word lines.   
     
     
         17 . The flash memory device of  claim 16 , wherein a distance between the ground selection line and a word line adjacent to the ground selection line is greater than the distance between a pair of adjacent word lines. 
     
     
         18 . The flash memory device of  claim 17 , wherein each of the distance between the string selection line and the word line adjacent to the string selection line, and the distance between the ground selection line and the word line adjacent to the ground selection line is equal to two times the distance between a pair of adjacent word lines. 
     
     
         19 . The flash memory device of  claim 16 , wherein a distance between the string selection line and the ground selection line is equal to (the total number of word lines+1) multiplied by the distance of one pitch. 
     
     
         20 . The flash memory device of  claim 16 , wherein the string selection line, the ground selection line and each of the word lines are formed using double patterning technology. 
     
     
         21 . A method of manufacturing a flash memory device, the method comprising.
 forming a conductive layer on a substrate;   forming a hard mask layer on the conductive layer,   forming a first material layer on the hard mask layer;   forming photoresist patterns on the first material layer,   forming first material patterns, which selectively exposes a surface of the hard mask layer, through patterning using the photoresist patterns as an etching mask;   removing the photoresist patterns;   forming a second material layer on the first material patterns and the hard mask layer, the surface of which is selectively exposed;   forming a third material layer on the second material layer,   forming third material patterns, which is formed to expose an upper surface of the second material layer existing between portions of the second material layer, through patterning   selectively exposing surfaces of the first material patterns, the third material patterns and the hard mask layer by vertically removing the second material layer, the upper portion of which is exposed, thus forming second material patterns remaining only under the third material patterns;   forming hard mask patterns through patterning of the hard mask layer, the surface of which has been selectively exposed, using the first material patterns and the third material patterns as an etching mask;   removing the first material patterns, the second material patterns and the third material patterns;   forming conductive patterns through patterning of the conductive layer using the hard mask patterns as an etching mask; and   removing the hard mask patterns,   wherein the formed conductive patterns comprise a string selection line, a ground selection line, and a plurality of word lines formed between the string selection line and the ground selection line,   wherein a width of each of the word lines is formed to be greater than a distance between a pair of adjacent word lines,   wherein there are an odd number of word lines, and   wherein one of the plurality of word lines is formed adjacent to the ground selection line and is not involved in storage of information.   
     
     
         22 . A method of manufacturing a flash memory device, the method comprising:
 forming a conductive layer on a substrate;   forming a hard mask layer on the conductive layer;   forming a first material layer on the hard mask layer;   forming photoresist patterns on the first material layer,   forming first material patterns, which selectively exposes a surface of the hard mask layer, through patterning using the photoresist patterns as an etching mask;   removing the photoresist patterns;   forming a second material layer on the first material patterns and the hard mask layer, the surface of which is selectively exposed;   forming a third material layer on the second material layer,   forming third material patterns, which is formed to expose an upper surface of the second material layer existing between portions of the second material layer, through patterning;   selectively exposing surfaces of the first material patterns, the third material patterns and the hard mask layer by vertically removing the second material layer, the upper portion of which is exposed, thus forming second material patterns remaining only under the third material patterns;   forming hard mask patterns through patterning of the hard mask layer, the surface of which has been selectively exposed, using the first material patterns and the third material patterns as an etching mask;   removing the first material patterns, the second material patterns and the third material patterns;   forming conductive patterns through patterning of the conductive layer using the hard mask patterns as an etching mask; and   removing the hard mask patterns,   wherein the formed conductive patterns comprise a string selection line, a ground selection line, and a plurality of word lines formed between the string selection line and the ground selection line,   wherein a width of each of the word lines is formed to be greater than a distance between a pair of adjacent word lines,   wherein there are an odd number of word lines, and   wherein one of the plurality of word lines is formed adjacent to the string selection line are not involved in storage of information, and two of the plurality of word lines are formed adjacent to the ground selection line and are not involved in storage of information.   
     
     
         23 . A method of manufacturing a flash memory device, the method comprising:
 forming a conductive layer on a substrate;   forming a hard mask layer on the conductive layer;   forming a first material layer on the hard mask layer, forming photoresist patterns on the first material layer,   forming first material patterns, which selectively exposes a surface of the hard mask layer, through patterning using the photoresist patterns as an etching mask;   removing the photoresist patterns;   forming a second material layer on the first material patterns and the hard mask layer, the surface of which is selectively exposed;   forming a third material layer on the second material layer;   forming third material patterns, which is formed to expose an upper surface of the second material layer existing between portions of the second material layer, through patterning;   selectively exposing surfaces of the first material patterns, the third material patterns and the hard mask layer by vertically removing the second material layer, the upper portion of which is exposed, thus forming second material patterns remaining only under the third material patterns;   forming hard mask patterns through patterning of the hard mask layer, the surface of which has been selectively exposed, using the first material patterns and the third material patterns as an etching mask;   removing the first material patterns, the second material patterns and the third material patterns;   forming conductive patterns through patterning of the conductive layer using the hard mask patterns as an etching mask; and   removing the hard mask patterns,   wherein the formed conductive patterns comprise a string selection line, a ground selection line, and a plurality of word lines formed between the string selection line and the ground selection line,   the method further comprising, after forming the conductive patterns, trimming a portion of the string selection line adjacent to a word line.   
     
     
         24 . A method of manufacturing a flash memory device, the method comprising:
 forming first mask patterns for forming a string selection line, a ground selection line, and more than half of a plurality of word lines to be formed between the string selection line and the ground selection line;   forming second mask patterns for forming word lines of the plurality of word lines that are not formed by the first mask pattern between the first mask patterns; and   forming the string selection line, the ground selection line and the plurality of word lines using the first mask patterns and the second mask patterns as a patterning mask,   wherein a width of each of the word lines is greater than a distance between a pair of adjacent word lines, and   wherein there are an even number of word lines and each of the first mask patterns and the second mask patterns forms an identical number of word lines.   
     
     
         25 . The method of  claim 24 , wherein a distance between the string selection line and a word line adjacent to the string selection line is equal to two times the distance between a pair of adjacent word lines and a distance between the ground selection line and a word line adjacent to the ground selection line is also equal to two times the distance between the pair of adjacent word lines.