Method of fabricating semiconductor device

A method of fabricating a semiconductor device, the method comprising:

• providing a substrate including a cell region and a peripheral region that surrounds the cell region;
• forming a cell gate structure on the cell region of the substrate;
• forming a peripheral gate structure on the peripheral region of the substrate;
• forming a bit-line structure on the cell region of the substrate;
• forming a preliminary pad layer that covers the bit-line structure and the peripheral gate structure;
• and
• etching the preliminary pad layer,
• wherein etching the preliminary pad layer includes:
• forming a first mask structure on the preliminary pad layer;
• simultaneously forming on the first mask structure a line mask pattern that overlaps the cell region and a peripheral mask pattern that overlaps the peripheral region;
• and
• etching the line mask pattern to form a plurality of cell mask patterns.

A method of fabricating a semiconductor device, the method comprising:

• providing a substrate including a cell region and a peripheral region that surrounds the cell region;
• forming a cell gate structure on the cell region;
• forming a peripheral gate structure on the peripheral region;
• forming a bit-line structure on the cell region;
• forming a preliminary pad layer that covers the bit-line structure and the peripheral gate structure;
• and
• etching the preliminary pad layer to form a landing pad and a peripheral conductive pad,
• wherein etching the preliminary pad layer includes:
• forming a first mask structure on the preliminary pad layer;
• forming a second mask structure on the first mask structure;
• forming a first photoresist layer on the second mask structure;
• using the first photoresist layer as an etching mask to etch the second mask structure;
• forming a line mask pattern and a peripheral mask pattern on the first mask structure;
• forming a third mask structure on the line mask pattern and the peripheral mask pattern;
• forming a second photoresist layer on the third mask structure;
• using the second photoresist layer as an etching mask to etch the third mask structure;
• etching the line mask pattern to form a cell mask pattern;
• using the cell mask pattern and the peripheral mask pattern as an etching mask to etch the first mask structure;
• and
• using the etched first mask structure as an etching mask to etch the preliminary pad layer,
• wherein the first photoresist layer includes:
• a first line opening that overlaps the cell region;
• and
• a peripheral resist pattern that overlaps the peripheral region,
• wherein the second photoresist layer includes a second line opening that overlaps the cell region, and
• wherein an extending direction of the first line opening and an extending direction of the second line opening are crossing each other.