The novel SCR-based ESD protection device with high holding voltage

Abstract

This paper introduces a novel silicon controlled rectifier (SCR)-based device for ESD power clamp and I/O clamp. The device obtained the high holding voltage and low triggering voltage by adding a p-drift junction and n-well in the cathode region. These characteristics enable latch-up immune normal operation as well as superior full chip ESD protection. The proposed device is designed by compatible 0.35um BCD(Bipolar-CMOS-DMOS) technology. We investigated electrical characteristic by measurement and TCAD simulation. In the measurement result, the proposed device has triggering voltage of 12.8V and holding voltage of 10V. The proposed device has high holding voltage as well as high robustness and second breakdown current. (It2=67.4mA/um)

Design of ESD protection with SCR-based structures for latch-up immunity

“…Proposed SCR-based ESD protection circuit was transformed for power clamp by extending P+ (P-drift) cathode region across the first N-well as shown in Fig. 2 [7]. P-drift region is formed to reduce trigger voltage and increase the holding voltage.…”

Simple scheme to increase hold voltage for silicon‐controlled rectifier

“…To prevent the chip malfunction caused by SCR turn‐on, various schemes have been proposed to increase the hold voltage of an SCR. The schemes include increasing the space between the anode and the cathode [5], adding series diodes [6, 7], stacking another SCR [8], placing the base before the emitter [9] and adding additional implants on the wells [10]. In this Letter, another approach is proposed to increase the hold voltage of an SCR and their high‐current behaviours are discussed based on the fundamental latch‐up theory.…”