Method of manufacturing semiconductor device
View Patent ↗A method of manufacturing a semiconductor device of the present invention consists of forming a trench in a trench-type cell transistor region; forming a gate insulating film and a gate material layer on a semiconductor substrate; forming a photoresist layer on the semiconductor substrate so as to expose extension region formation portions of the trench-type cell transistor region and a high breakdown voltage transistor region; forming extension regions in each region by performing ion implantation in the semiconductor substrate surface of the trench-type cell transistor region and the high breakdown voltage transistor region and then patterning gates, and forming extension regions of an ordinary breakdown voltage transistor by covering the trench-type cell transistor region and the high breakdown voltage transistor region with a photoresist layer and implanting ions in the ordinary breakdown voltage transistor region.
1. A method of manufacturing a semiconductor device in which a trench-type transistor, a high breakdown voltage transistor, and an ordinary breakdown voltage transistor are provided on a semiconductor substrate, comprising the steps of:
forming element isolation layers on a surface of a semiconductor substrate for isolating a trench-type transistor, a high breakdown voltage transistor, and an ordinary breakdown voltage transistor;
forming a trench in a trench-type transistor region;
forming a gate insulating film and a gate material layer on the semiconductor substrate and in the trench;
forming a first photoresist layer on the semiconductor substrate so as to expose extension region formation portions of the trench-type transistor region and the high breakdown voltage transistor region;
forming extension regions of the trench-type transistor and the high breakdown voltage transistor by performing ion implantation in the trench-type transistor region and the high breakdown voltage transistor region;
forming a second photoresist layer on the semiconductor substrate so as to cover the trench-type transistor region and the high breakdown voltage transistor region and expose the ordinary breakdown voltage transistor region; and
forming extension regions of the ordinary breakdown voltage transistor by implanting ions in the ordinary breakdown voltage transistor region.
2. The method of manufacturing a semiconductor device according to claim 1 , wherein ion implantation is performed in the extension region formation portions after covering the ordinary breakdown voltage transistor region and a channel portion of the high breakdown voltage transistor region with a photoresist layer.
3. The method of manufacturing a semiconductor device according to claim 1 , wherein gate electrodes are formed by patterning the gate insulating film and the gate material layer after forming the extension regions in the trench-type transistor region and the high breakdown voltage transistor region.