| Title |
SCR-Based ESD Protection Device with an Added Metal Discharge Path for 5-V Applications |
| Authors |
(Dong-Hyeon Kim) ; (Jae-Yoon Oh) ; (Min-Seo Kim) ; (Cheon-Hoo Jeon) ; (Jung-Won Kang) ; (Yong-Seo Koo) |
| DOI |
https://doi.org/10.5573/JSTS.2026.26.1.81 |
| Keywords |
Avalanche breakdown; positive feedback; SCR (silicon controlled rectifier); LVTSCR (low voltage; trigger SCR); holding voltage |
| Abstract |
This study proposed a new ESD protection device structure to improve the low holding voltage issue of conventional SCR and LVTSCR devices. The proposed structure incorporates a heavily doped P+ region between the wells to lower the trigger voltage and introduces an additional metal path to form a new discharge route for the parasitic NPN BJT, thereby reducing the positive feedback loop gain and increasing the holding voltage. The operating principle of the proposed device was verified through TCAD simulation, and the design was implemented using a 0.18 μm BCD process. The results confirmed that the proposed device exhibits a higher holding voltage compared to conventional SCR and LVTSCR structures under identical conditions. Consequently, the proposed ESD protection device is suitable for protecting IC circuits operating at 5 V. In addition, an extra PNP BJT discharge path was added at the anode to enhance the current driving capability. TLP measurement results showed that the Ron value decreased, leading to an increase in It2 , confirming that this design effectively improves the current handling capability. Finally, the design parameter D1 was introduced to investigate the electrical characteristics with respect to length variation.As D1 increased, the holding voltage was further improved, which was attributed to the reduction in current gain (β) and loop gain of the parasitic PNP BJT.Therefore, optimizing the length of D1 was found to be an effective design approach that directly contributes to enhancing the holding voltage of the device. |