Patent attributes
An ESD protection device includes: a semiconductor substrate of a first conductivity type having a first major surface and a second major surface; a signal input electrode formed on the first major surface of the semiconductor substrate; a base region of a second conductivity type formed on a surface region of the second major surface of the semiconductor substrate; a diffusion region of the first conductivity type; a resistor layer formed on the second major surface of the semiconductor substrate of the first conductivity type; a signal output electrode electrically connected to the diffusion region of the first conductivity type; and a ground electrode electrically connected to the resistor layer. The diffusion region is selectively formed on a surface region of the base region of the second conductivity type in the semiconductor substrate of the first conductivity type. The resistor layer is electrically connected to the diffusion region of the first conductivity type.