SEMICONDUCTOR DEVICE PROVIDED WITH MASK ROM, AND METHOD OF FABRICATING SAME

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor device provided with a mask ROM adapted such that threshold voltages of mask ROM transistors may be adjustable, and to provide a method of fabricating the device.

SOLUTION: The mask ROM device has: a semiconductor substrate 100; component isolation film patterns 110 that define a plurality of active regions on the semiconductor substrate; a mask ROM region MRR formed on each active region and made up of a normally-on transistor and a normally-off transistor; gate lines 170 that are laid out on the active regions and extend across over the component isolation film patterns 110; and gate insulating films 121, 160 formed between the gate lines 170 and the active region. The normally-off transistor further has a floating conductive pattern 131 and an inter-gate insulating film pattern 141 stacked in series between the gate line and the gate insulating film 190.

COPYRIGHT: (C)2007,JPO&INPIT