| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a semiconductor device capable of accomplishing a desired threshold voltage while suppressing reduction of reliability and variation of device. <P>SOLUTION: A semiconductor device 500 having a plurality of threshold voltages, according to an embodiment, includes a substrate 502, a first transistor 510 placed on the substrate having a first threshold voltage, a second transistor 530 placed on the substrate having a second threshold voltage. The first transistor includes a first interface layer 516 formed on a first channel region of the substrate, a first gate dielectric layer 518 formed on the first interface layer, first gate electrodes 520, 522 formed on the first gate dielectric layer. The second transistor includes a second interface layer 536 formed on a second channel region of the substrate, a second gate dielectric layer 538 formed on the second interface layer, second gate electrodes 540, 542 formed on the second gate dielectric layer. The second interface layer does not exist in the first interface layer, and includes an additional element different from Si, O, and N. The first threshold voltage is different from the second threshold voltage. The first transistor and second transistor have the same conductivity type. <P>COPYRIGHT: (C)2012,JPO&INPIT |
