NAND-TYPE NON-VOLATILE MEMORY DEVICES AND METHODS OF FABRICATING THE SAME

摘要

A NAND type nonvolatile memory apparatus and its manufacturing method are provided to improve program disturbance characteristics and to increase a sensing margin by preventing sensing mis-operation during a reading operation. A string select transistor(SSL) and a ground select transistor(GSL) are formed on a semiconductor substrate(100). The string select transistor and the ground select transistor have select source/drain regions(120,130,140,150) that are separated from each other. Plural memory cell transistors(MT1-MTn) are formed on the semiconductor substrate between the string select transistor and the ground select transistor. The memory cell transistors are connected in serial to each other. The memory cell transistors have cell source/drain regions(160) that are separated from each other. A recess region(180) is formed on at least one of the select drain region of the ground select transistor and the select source region of the string select transistor. Impurity concentrations of the select drain region of the ground select transistor and the select source region of the string select transistor are different from at least one impurity concentration of the cell source/drain regions.