Other

Zi-Ping Chen

Ming-Dou Ker

Hsin-Chin Jiang

Ming-Dao Ker

Diode strings and electrostatic discharge circuits characterized by low current leakage. Each diode region provides a diode and has first and second regions. The first region is of a first conductive type and formed on a substrate, acting as a first electrode of a diode. The second region is of a second conductive type opposite to the first conductive type, formed in the first region and acting as a second electrode of a corresponding diode. The diodes are forward connected in series to form major anode and cathode of the diode string. An isolation region is of the second conductive type to isolate those diode regions. A bias resistor is connected between the isolation region and a first power line. During normal operation, the voltage of the first power line is not within the range between the voltages of the major anode and cathode.

Diode strings and electrostatic discharge protection circuits

A diode with low substrate current leakage and suitable for BiCMOS process technology. A buried layer is formed on a semiconductor substrate. A connection region and well contact the buried layer. Isolation regions are adjacent to two sides of the buried layer, each deeper than the buried layer. The isolation regions and the buried layer isolate the connection zone and the well from the substrate. The first doped region in the well is a first electrode. The well and the connection region are electrically connected, acting as a second electrode.

Diode and applications thereof

An ESD protection circuit that protects a mixed-voltage input/output (I/O) buffer circuit in an integrated circuit is provided. The ESD protection circuit includes an ESD discharging circuit coupled to the I/O pad and ESD detection circuit coupled to the discharging circuit providing a means for detecting an ESD and triggering the discharging circuit to conduct the ESD to ground. The ESD discharging circuit comprises stacked NMOS transistors or a field oxide device (FOD). The protection circuit can also be used in an ESD protection circuit for a high-voltage-tolerant input pad or to protect multiple input pads and/or multiple I/O pads in an integrated circuit.

Growing community of inventors

Shindian, Taiwan

Zi-Ping Chen