| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a semiconductor device related to an LDMOS transistor, which achieves a high-speed operation. <P>SOLUTION: A semiconductor device comprises an opening trench 5 at the center part of each two of a plurality of element isolation films 4 formed on a surface of a P-type well layer 3, a gate electrode 7 formed on the opening trench 5 via a gate insulator 6 so as to extend from a side wall of the opening trench 5 toward the inside of the opening trench 5, a P-type body layer 8 formed on the P-type well layer 3 in the opening trench 5 in self-alignment with an oblique rotation ion implantation of boron by applying the gate electrode 7 as a mask, an N<SP POS="POST">+</SP>-type source layer 9 formed on the P-type body layer 8 with ion implantation of arsenic by applying the gate electrode 7 as a mask, an N<SP POS="POST">+</SP>-type drain layer 10 formed on the P-type well layer 3 between the element isolation films 4 concurrently with the formation of the N<SP POS="POST">+</SP>-type source layer 9, and an N<SP POS="POST">-</SP>-type drift layer formed on the P-type well layer 3 under the element isolation film 4 so as to extend from an edge portion of the P-type body layer 8 to the N<SP POS="POST">+</SP>-type drain layer 10. A width of the N<SP POS="POST">-</SP>-type drain layer 11 in a region A from the edge portion of the P-type body layer 8 to a lower portion of the side wall of the opening trench 5 is controlled to become as narrow as possible. <P>COPYRIGHT: (C)2012,JPO&INPIT |
