A Novel Bidirectional AlGaN/GaN ESD Protection Diode

Abstract

Despite the superior working properties, GaN-based HEMTs and systems are still confronted with the threat of a transient ESD event, especially for the vulnerable gate structure of the p-GaN or MOS HEMTs. Therefore, there is still an urgent need for a bidirectional ESD protection diode to improve the ESD robustness of a GaN power system. In this study, an AlGaN/GaN ESD protection diode with bidirectional clamp capability was proposed and investigated. Through the combination of two floating gate electrodes and two pF-grade capacitors connected in parallel between anode or cathode electrodes and the adjacent floating gate electrodes (CGA (CGC)), the proposed diode could be triggered by a required voltage and possesses a high secondary breakdown current (IS) in both forward and reverse transient ESD events. Based on the experimental verification, it was found that the bidirectional triggering voltages (Vtrig) and IS of the proposed diode were strongly related to CGA (CGC). With CGA (CGC) increasing from 5 pF to 25 pF, Vtrig and IS decreased from ~18 V to ~7 V and from ~7 A to ~3 A, respectively. The diode’s high performance demonstrated a good reference for the ESD design of a GaN power system.

A Novel AlGaN/GaN Transient Voltage Suppression Diode with Bidirectional Clamp Capability

“…All the proposed B-TVS-D possess a high I S over than 8 A. Correspondingly, the equivalent HBM failure voltage (V HBM = I S × 1500 Ω) of the proposed B-TVS-D reaches to 12 kV; the value is higher than that of the bidirectional TVS diode in our previous work [19]. For the bidirectional AlGaN/GaN TVS diode in our previous work, both its V trig and I S are dependent on its capacitor.…”

“…It is obvious that the unidirectional TVS diode can be fabricated on the conventional p-GaN HEMT platform. TVS diode with the capability of bidirectional transient voltage suppression is needed [19]. To achieve this goal, we have proposed a bidirectional AlGaN/GaN TVS diode, which possesses a symmetrical triggering voltage (Vtrig) and a high secondary breakdown current (Is) in different directional electrostatic discharge events [19].…”

“…In this connection, Yajie Xin has proposed a unidirectional AlGaN/GaN transient voltage suppression (TVS) diode [18], which can be self-triggered by a desirable value in the unidirectional transient ESD event. However, in some fields, namely AC circuit and communication systems, a TVS diode with the capability of bidirectional transient voltage suppression is needed [19]. To achieve this goal, we have proposed a bidirectional AlGaN/GaN TVS diode, which possesses a symmetrical triggering voltage (V trig ) and a high secondary breakdown current (I s ) in different directional electrostatic discharge events [19].…”

“…However, in some fields, namely AC circuit and communication systems, a TVS diode with the capability of bidirectional transient voltage suppression is needed [19]. To achieve this goal, we have proposed a bidirectional AlGaN/GaN TVS diode, which possesses a symmetrical triggering voltage (V trig ) and a high secondary breakdown current (I s ) in different directional electrostatic discharge events [19]. However, to obtain a required triggering voltage, a relatively large capacitor is needed, which will also obviously decrease the I s of the bidirectional AlGaN/GaN TVS diode; i.e., the protection capability of that bidirectional AlGaN/GaN TVS diode will be obviously weakened, as described in our previous work.…”

Experimental Investigation and Model Analysis on a GaN Electrostatic Discharge Clamp

“…Based on the above reasons, we carried out the experimental investigation and model analysis on the GaN ESD clamp. Similar to our previous work [18][19], for reducing the experimental cost, the equivalent structure made up of the chip resistor and p-GaN HEMTs (EPC2036) [20] is employed to carry out the experimental investigation. As noted, due to the lack of commercial GaN L-FER, L-FER in GaN ESD clamp is also made up of commercial p-GaN HEMT (EPC2036).…”