Semiconductor device

A semiconductor device comprising:

• a substrate comprising a first region, a second region, a third region, and a fourth region;
• a gate insulating layer on the first region, the second region, the third region, and the fourth region;
• a first work function adjusting layer and a polysilicon layer on the first region;
• a second work function adjusting layer on the first and second regions;
• a third work function adjusting layer on the first region, the second region, and the third region;
• and
• a gate electrode layer on the first region, the second region, the third region, and the fourth region.

A semiconductor device comprising:

• a first fin-type transistor, a second fin-type transistor, a third fin-type transistor, and a fourth fin-type transistor that are on a substrate,
• wherein the first fin-type transistor, the second fin-type transistor, the third fin-type transistor, and the fourth fin-type transistor have different respective threshold voltages,
• wherein the first fin-type transistor comprises a first gate insulating layer, a first material layer, and a first gate electrode layer,
• wherein the second fin-type transistor comprises a second gate insulating layer, a second material layer, and a second gate electrode layer,
• wherein the second material layer is thinner than the first material layer,
• wherein the third fin-type transistor comprises a third gate insulating layer, a third material layer, and a third gate electrode layer,
• wherein the third material layer is thinner than the second material layer,
• wherein the fourth fin-type transistor comprises a fourth gate insulating layer and a fourth gate electrode layer, and
• wherein the first material layer comprises a lower metal layer, an upper metal layer, and a polysilicon layer between the lower metal layer and the upper metal layer.