| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a semiconductor device which, although capable of mixed mounting of a VFET and other kinds of elements on a semiconductor substrate, does not have a significant difference in grade on the surfaces of semiconductor layers laminated on the semiconductor substrate. <P>SOLUTION: On a P-type silicon substrate 2 are laminated a box layer 3 consisting of silicon oxide, an N<SP POS="POST">+</SP>type lateral direction conductive layer 4 and an N<SP POS="POST">-</SP>type surface layer 5. On the box layer 3 is formed a deep trench 6 shaped like a ring in a plan view, which has a depth ranging from the surface of the N<SP POS="POST">-</SP>type surface layer 5 to the box layer 3. A transistor formation region 8 surrounded by the deep trench 6 and the box layer 3 is isolated from the periphery thereof. It is in this transistor formation region 8 that a source region 14 and a drain region 16 are formed in the surface layer part of the N<SP POS="POST">-</SP>type surface layer 5. Also, an N<SP POS="POST">+</SP>type longitudinal direction conductive layer 17, connected to the drain region 16 and the N<SP POS="POST">+</SP>type lateral direction conductive layer 4, is formed along the side surface of the deep trench 6. <P>COPYRIGHT: (C)2013,JPO&INPIT |
