A structure of field-effect transistor includes a silicon layer of a silicon-on-insulator structure. A gate structure layer in a line shape is disposed on the silicon layer, wherein the gate structure layer includes a first region and a second region abutting to the first region. Trench isolation structures in the silicon layer are disposed at two sides of the gate structure layer, corresponding to the second region. The second region of the gate structure layer is disposed on the silicon layer and overlaps with the trench isolation structure. A source region and a drain region are disposed in the silicon layer at the two sides of the gate structure layer, corresponding to the first region. The second region of the gate structure layer includes a conductive-type junction portion.

A structure of field-effect transistor includes a silicon layer of a silicon-on-insulator structure. A gate structure layer in a line shape is disposed on the silicon layer, wherein the gate structure layer includes a first region and a second region abutting to the first region. Trench isolation structures in the silicon layer are disposed at two sides of the gate structure layer, corresponding to the second region. The second region of the gate structure layer is disposed on the silicon layer and overlaps with the trench isolation structure. A source region and a drain region are disposed in the silicon layer at the two sides of the gate structure layer, corresponding to the first region. The second region of the gate structure layer includes a conductive-type junction portion.

A method for fabricating a field-effect transistor includes the following steps. A gate structure layer in a line shape including a first region and a second region abutting to the first region is formed on a silicon layer. A first implanting process is performed to implant first-type dopants at least into a second portion of the second region of the gate structure layer. A second implanting region is performed to implant second-type dopants into the silicon layer to form a source region and a second region corresponding to the first region of the gate structure layer. The gate structure layer has a conductive-type junction at an interface between the first and second portions of the second region. A width of the silicon layer under the second region of the gate structure layer is smaller than a width of the gate structure layer.

A method for fabricating a field-effect transistor includes the following steps. A gate structure layer in a line shape including a first region and a second region abutting to the first region is formed on a silicon layer. A first implanting process is performed to implant first-type dopants at least into a second portion of the second region of the gate structure layer. A second implanting region is performed to implant second-type dopants into the silicon layer to form a source region and a second region corresponding to the first region of the gate structure layer. The gate structure layer has a conductive-type junction at an interface between the first and second portions of the second region. A width of the silicon layer under the second region of the gate structure layer is smaller than a width of the gate structure layer.

An integrated circuit (IC) structure includes two active areas extending in a first direction, two gate structures extending in a second direction, a first metal segment extending in the second direction in a first metal layer, second and third metal segments extending in the first direction in a second metal layer, and a gate via structure extending from the third metal segment to one of the gate structures. The gate structures overlie the active areas, the first metal segment overlies each of the active areas between the gate structures, the second metal segment overlies a first active area and overlies and is electrically connected to the first metal segment, and the first and second metal segments are electrically connected to the second active area, isolated from the first active area between the gate structures, and connected to the first active area outside the gate structures.

An integrated circuit (IC) structure includes two active areas extending in a first direction, two gate structures extending in a second direction, a first metal segment extending in the second direction in a first metal layer, second and third metal segments extending in the first direction in a second metal layer, and a gate via structure extending from the third metal segment to one of the gate structures. The gate structures overlie the active areas, the first metal segment overlies each of the active areas between the gate structures, the second metal segment overlies a first active area and overlies and is electrically connected to the first metal segment, and the first and second metal segments are electrically connected to the second active area, isolated from the first active area between the gate structures, and connected to the first active area outside the gate structures.

The present disclosure provides a method, which includes forming a first fin structure and a second fin structure over a substrate, which has a first trench positioned between the first and second fin structures. The method also includes forming a first dielectric layer within the first trench, recessing the first dielectric layer to expose a portion of the first fin structure, forming a first capping layer over the exposed portion of the first fin structure and the recessed first dielectric layer in the first trench, forming a second dielectric layer over the first capping layer in the first trench while the first capping layer covers the exposed portion of the first fin feature and removing the first capping layer from the first fin structure.

A structure of field-effect transistor includes a silicon layer of a silicon-on-insulator structure. A gate structure layer in a line shape is disposed on the silicon layer, wherein the gate structure layer includes a first region and a second region abutting to the first region. Trench isolation structures in the silicon layer are disposed at two sides of the gate structure layer, corresponding to the second region. The second region of the gate structure layer is disposed on the silicon layer and overlaps with the trench isolation structure. A source region and a drain region are disposed in the silicon layer at the two sides of the gate structure layer, corresponding to the first region. The second region of the gate structure layer includes a conductive-type junction portion.

A structure of field-effect transistor includes a silicon layer of a silicon-on-insulator structure. A gate structure layer in a line shape is disposed on the silicon layer, wherein the gate structure layer includes a first region and a second region abutting to the first region. Trench isolation structures in the silicon layer are disposed at two sides of the gate structure layer, corresponding to the second region. The second region of the gate structure layer is disposed on the silicon layer and overlaps with the trench isolation structure. A source region and a drain region are disposed in the silicon layer at the two sides of the gate structure layer, corresponding to the first region. The second region of the gate structure layer includes a conductive-type junction portion.

A structure of field-effect transistor includes a silicon layer of a silicon-on-insulator structure. A gate structure layer in a line shape is disposed on the silicon layer, wherein the gate structure layer includes a first region and a second region abutting to the first region. Trench isolation structures in the silicon layer are disposed at two sides of the gate structure layer, corresponding to the second region. The second region of the gate structure layer is disposed on the silicon layer and overlaps with the trench isolation structure. A source region and a drain region are disposed in the silicon layer at the two sides of the gate structure layer, corresponding to the first region. The second region of the gate structure layer includes a conductive-type junction portion.