Dongyan Zhao , Yipeng Chen , Shicong Zhou , Xinyu Zhu , Yidong Yuan , Yi Hu , Tianting Zhao , Xiaojuan Li , Shurong Dong
{"title":"Investigation on MOS shunt LVTSCR for ESD application","authors":"Dongyan Zhao , Yipeng Chen , Shicong Zhou , Xinyu Zhu , Yidong Yuan , Yi Hu , Tianting Zhao , Xiaojuan Li , Shurong Dong","doi":"10.1016/j.sse.2024.108963","DOIUrl":null,"url":null,"abstract":"<div><p>Continuously scaling down ICs result in more stringent electrostatic discharge (ESD) protection design requirements. Compared with other devices, silicon-controlled rectifier (SCR) has become the first choice for its area efficiency and robustness. In order to improve the latch-up issue of SCR, various schemes have been proposed. A simple method is to extend the SCR path length, which will result in the enlarged ON resistance. Segment technology is also used to improve the holding voltage of SCR, but it will shrink the effective emitter area and lead to the serious degradation of ESD robustness. MS-LVTSCR is used to protect CMOS input ports. The circuit operating voltage is 3.3V and the gate oxide DC breakdown voltage is 19V so that considering the safety margin, the ESD window is from 3.63V to 17.1V. This work proposes a novel MOS shunt low-voltage trigger silicon-controlled rectifier (MS-LVTSCR) electrostatic discharge protection device by inserting an embedded PMOS structure. Compared with the conventional LVTSCR, the proposed MS-LVTSCR achieves 53% improvement in the holding voltage and still maintains high ESD robustness with a current level of 31.5 mA/<span><math><mi>μ</mi></math></span>m without more device area consumption. In addition, both the TCAD simulation and theoretical analysis were carried out to explore the principle of current shunt effect to improve holding voltage. The extra shunt paths will weaken the conductance modulation effect of the main drift region in the main SCR path and its holding voltage can be further raised by reducing the proportion of main drift region current in the total current. We also conducted detailed studies on the mechanisms and geometry effects of this newly proposed structure via experimental validations.</p></div>","PeriodicalId":21909,"journal":{"name":"Solid-state Electronics","volume":null,"pages":null},"PeriodicalIF":1.4000,"publicationDate":"2024-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Solid-state Electronics","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0038110124001126","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ENGINEERING, ELECTRICAL & ELECTRONIC","Score":null,"Total":0}
引用次数: 0
Abstract
Continuously scaling down ICs result in more stringent electrostatic discharge (ESD) protection design requirements. Compared with other devices, silicon-controlled rectifier (SCR) has become the first choice for its area efficiency and robustness. In order to improve the latch-up issue of SCR, various schemes have been proposed. A simple method is to extend the SCR path length, which will result in the enlarged ON resistance. Segment technology is also used to improve the holding voltage of SCR, but it will shrink the effective emitter area and lead to the serious degradation of ESD robustness. MS-LVTSCR is used to protect CMOS input ports. The circuit operating voltage is 3.3V and the gate oxide DC breakdown voltage is 19V so that considering the safety margin, the ESD window is from 3.63V to 17.1V. This work proposes a novel MOS shunt low-voltage trigger silicon-controlled rectifier (MS-LVTSCR) electrostatic discharge protection device by inserting an embedded PMOS structure. Compared with the conventional LVTSCR, the proposed MS-LVTSCR achieves 53% improvement in the holding voltage and still maintains high ESD robustness with a current level of 31.5 mA/m without more device area consumption. In addition, both the TCAD simulation and theoretical analysis were carried out to explore the principle of current shunt effect to improve holding voltage. The extra shunt paths will weaken the conductance modulation effect of the main drift region in the main SCR path and its holding voltage can be further raised by reducing the proportion of main drift region current in the total current. We also conducted detailed studies on the mechanisms and geometry effects of this newly proposed structure via experimental validations.
期刊介绍:
It is the aim of this journal to bring together in one publication outstanding papers reporting new and original work in the following areas: (1) applications of solid-state physics and technology to electronics and optoelectronics, including theory and device design; (2) optical, electrical, morphological characterization techniques and parameter extraction of devices; (3) fabrication of semiconductor devices, and also device-related materials growth, measurement and evaluation; (4) the physics and modeling of submicron and nanoscale microelectronic and optoelectronic devices, including processing, measurement, and performance evaluation; (5) applications of numerical methods to the modeling and simulation of solid-state devices and processes; and (6) nanoscale electronic and optoelectronic devices, photovoltaics, sensors, and MEMS based on semiconductor and alternative electronic materials; (7) synthesis and electrooptical properties of materials for novel devices.