Semiconductor device with pad electrode

A semiconductor device comprising:

• a semiconductor substrate of a first conductivity type;
• an epitaxial layer of a second conductivity type formed on a surface of the semiconductor substrate, said epitaxial layer including first and second regions;
• a semiconductor layer of the first conductivity type, formed in the epitaxial layer, for isolating the first region from the second region, said first region including a first resistance;
• an insulating film formed on the epitaxial layer;
• a pad electrode formed on the insulating film and located above the first region;
• and
• a resistor layer, formed on the insulating film and located above the second region, one end of the resistor layer being connected to the first region through said insulating film and another end of the resistor layer being connected to a power source,
• wherein the resistor has a resistance value great enough to attenuate ripples transmitted from the power source, and
• wherein the resistance value is greater than an impedance of a capacitor formed by the pad electrode, the insulating film and the first region.

A semiconductor device comprising:

• a semiconductor substrate of a first conductivity type;
• an epitaxial layer of a second conductivity type formed on a surface of the semiconductor substrate, said epitaxial layer including first and second regions, said first region being a uniformly doped second conductivity layer;
• said second region of said epitaxial layer serving as an epitaxial resistor;
• an insulating film formed on the epitaxial layer;
• and
• a power source electrically connected to the second region of the epitaxial layer through said insulating film;
• and
• a bonding pad electrode formed on the insulating film and located above the first region of said epitaxial layer, said bonding pad electrode and said first region forming a capacitor using said insulating film as an insulator.

A semiconductor device comprising:

• a semiconductor substrate of a first conductivity type;
• an epitaxial layer of a second conductivity type formed on a surface of the semiconductor substrate, said epitaxial layer including first and second regions, said second region of said epitaxial layer serving as an epitaxial resistor;
• an insulating film formed on the epitaxial layer;
• a power source electrically connected to the second region of the epitaxial layer through said insulating film;
• a pad electrode formed on the insulating film and located above the first region of said epitaxial layer;
• wherein the second region of the epitaxial layer serving as the epitaxial resistor has a resistance value great enough to attenuate ripples transmitted from the power source, and
• wherein the resistance value is greater than an impedance of a capacitor formed by the pad electrode, the insulating film and the first region of the epitaxial layer.

A semiconductor device comprising:

• a semiconductor substrate of a first conductivity type;
• an epitaxial layer of a second conductivity type formed on a surface of the semiconductor substrate, said epitaxial layer including first and second regions, said second region of said epitaxial layer serving as an epitaxial resistor;
• an insulating film formed on the epitaxial layer;
• a power source electrically connected to the second region of the epitaxial layer through said insulating film;
• a pad electrode formed on the insulating film and located above the first region of said epitaxial layer, and
• wherein a width of the second region of the epitaxial layer is set narrower than that of the first region of the epitaxial layer.