A method for manufacturing a transient-voltage suppression device, the transient-voltage suppression device including a first diode, a second diode, and a zener diode, an electrical connection between an anode of the first diode and a cathode of the second diode being used as a first potential terminal, an electrical connection between a cathode of the first diode and a cathode of the zener diode being used as a second potential terminal, and an electrical connection between an anode of the second diode and an anode of the zener diode being used as a third potential terminal, wherein the method comprises:
- forming a mask layer on a substrate of a second conductivity type, and then performing lithography and etching the mask layer to expose a doping window of a first-conductivity-type well region;
- doping the substrate with first-conductivity-type ions through the doping window of the first-conductivity-type well region to form a first region on a surface of the substrate;
- growing an oxide layer as a doping blocking-layer in the first region;
- removing the mask layer, and doping areas of the surface of the substrate not covered by the doping blocking-layer with second-conductivity-type ions to form a second region, a first conductivity type and the second conductivity type being conductivity types opposite to each other;
- performing a thermal drive-in to enable the first region to diffuse to form a first well and a second well, and enable the second region to diffuse to form a third well and a fourth well, the third well being located between the first well and the second well to isolate the first well and the second well from each other, the second well being located between the third well and the fourth well;
- and
- forming, after the doping blocking-layer is removed, respectively a first doped region, a second doped region, a third doped region, a fourth doped region, a fifth doped region, a sixth doped region, and a zener diode active region by lithographing and doping;
- wherein the zener diode active region is located in the fourth well and is of the second conductivity type;
- the first doped region is of the first conductivity type and is located in the first well;
- the second doped region is of the second conductivity type and is disposed in the first well;
- the third doped region is of the first conductivity type and is disposed in the second well;
- the fourth doped region is of the second conductivity type and is disposed in the second well;
- the fifth doped region is of the first conductivity type and is disposed in the zener diode active region;
- and the sixth doped region is of the second conductivity type and is disposed in the zener diode active region;
- and
- wherein the Zener diode active region has a doping concentration different than that of the fourth well;
- wherein the Zener diode active region has phosphorus doping ions and boron doping ions, and a doping concentration of the phosphorus doping ions is less than that of the boron doping ions;
- wherein the first well and the second well are deep N-wells;
- the third well, the fourth well, and the fifth well are deep P-wells;
- and the first-conductivity-type well region and the second-conductivity-type well region are formed by drive-in a long time of 250 to 350 minutes at high temperatures of 1000 to 1300 degree Celsius.