Patent ID: 9105477
Filing Date: 2015-08-11
Classification: H01L

Abstract:
1. An electrostatic discharge (ESD) protection structure comprising: a semiconductor substrate including a first N-type well region and a first P-type well region, the first N-type well region including a first region and a second region, and the first P-type well region including a third region and a fourth region; a PMOS transistor located in the first region of the first N-type well region, the PMOS transistor including a gate located on the first N-type well region, and a source region and a drain region respectively located on both sides of the gate in the first N-type well region, the source region and the gate of the PMOS transistor being connected to a power supply terminal, and the drain region of the PMOS transistor being connected to an input and output (I/O) interface terminal; a first doped base region located in the second region of the first N-type well region, wherein the first doped base region is N-type doped and connected to an external trigger-voltage adjustment circuit, and wherein the external trigger-voltage adjustment circuit is configured to pull down an electric potential of the first doped base region when the power supply terminal generates an instantaneous electric potential difference; an NMOS transistor located in the third region of the first P-type well region, the NMOS transistor including a gate located on the first P-type well region, and a source region and a drain region respectively located on both sides of the gate in the first P-type well region, the drain region of the NMOS transistor being connected to the I/O interface terminal, and the gate and the source region of the NMOS transistor being connected to a ground terminal; and a second doped base region located in the fourth region of the first P-type well region, wherein the second doped base region is P-type doped and is connected to the external trigger-voltage adjustment circuit, and wherein the external trigger-voltage adjustment circuit is configured to pull up an electric potential of the second doped base region when the power supply terminal generates the instantaneous electric potential difference.