Semiconductor device and method of manufacturing the same
A thin film resistor includes a high-resistance region and low-resistance regions which are formed at both ends of the high-resistance region. The high-resistance region includes first high-resistance regions and a second high-resistance region, and the first high-resistance regions are arranged at both side surfaces in a first direction in the second high-resistance region. The second high-resistance region has a higher sheet resistance than that of the first high-resistance regions.
1. A semiconductor device, comprising:
a semiconductor substrate;
an insulating film formed on the semiconductor substrate;
first high-resistance regions constructed from a polysilicon film formed on the insulating film;
a second high-resistance region constructed from the polysilicon film formed on the insulating film, and having side surfaces in a first direction, the side surfaces being sandwiched by the first high-resistance regions; and
low-resistance regions constructed from the polysilicon film, formed on the insulating film, and arranged on both ends of the first high-resistance regions and the second high-resistance region in a second direction orthogonal to the first direction,
a sheet resistance of the second high-resistance region being higher than a sheet resistance of the first high-resistance regions.
2. The semiconductor device according to claim 1 , wherein the sheet resistance of the second high-resistance region is 10 times or more as high as the sheet resistance of the first high-resistance regions.
3. The semiconductor device according to claim 2 , wherein the first high-resistance regions and the second high-resistance region are constructed from the polysilicon film into which impurities of a first conductivity type are introduced.
4. The semiconductor device according to claim 2 , wherein the first high-resistance regions and the second high-resistance region are constructed from the polysilicon film into which impurities of a second conductivity type are introduced.
5. The semiconductor device according to claim 1 , wherein the first high-resistance regions and the second high-resistance region are constructed from the polysilicon film into which impurities of a first conductivity type are introduced.
6. The semiconductor device according to claim 1 , wherein the first high-resistance regions and the second high-resistance region are constructed from the polysilicon film into which impurities of a second conductivity type are introduced.
7. The semiconductor device according to claim 1 , wherein the second high-resistance region is constructed from a non-doped polysilicon film, and the first high-resistance regions are formed of the polysilicon film into which impurities of one of a first conductivity type and a second conductivity type are introduced.