Semiconductor device and manufacturing method thereof
View Patent ↗A semiconductor device comprises a field-effect transistor arranged in a semiconductor substrate, which transistor has a gate electrode, source/drain impurity diffusion regions, and carbon layers surrounding the source/drain impurity diffusion regions. Each of the carbon layers is provided at an associated of the source/drain impurity diffusion regions and positioned so as to be offset from the front edge of a source/drain extension in direction away from the gate electrode and to surround as profile the associated source/drain impurity diffusion region.
1. A semiconductor device including a field-effect transistor arranged in a semiconductor substrate, the transistor comprising:
a gate electrode;
a source/drain extension region in the semiconductor substrate;
a source/drain impurity diffusion region in the semiconductor substrate deeper than the source/drain extension region;
a carbon layer surrounding the source/drain impurity diffusion region; and
a pocket region located below the source/drain extension region,
wherein the carbon layer is offset from front edges of the source/drain extension region and the pocket region in the direction away from the gate electrode.
2. The semiconductor device according to claim 1 , wherein the source/drain impurity diffusion region is offset from a channel-side boundary of the carbon layer so as to be away from the gate electrode.
3. The semiconductor device according to claim 1 , wherein the carbon layer is positioned deeper in the semiconductor substrate than a bottom of the source/drain impurity diffusion region.
4. The semiconductor device according to claim 1 , further comprising:
a first sidewall spacer provided on a side face of the gate electrode; and
a second sidewall spacer covering the first sidewall spacer;
wherein the channel-side boundary of the carbon layer aligns with the first sidewall spacer, and the source/drain impurity diffusion region aligns with the second sidewall spacer.
5. The semiconductor device according to claim 1 , wherein at least a part of the source/drain extension region extends outside the carbon layer.