ESD 的HBM，MM，CDM考虑

IC2019

ESD设计过程中，怎么只考虑HBM，MM ,  CDM都不怎么考虑，这是为啥呢？MM的峰值电流不是更大，破坏力更大吗？

IC2019

另外，CDM的泄电通路都如何加？

wuzhuoqing

ESD  的HBM，MM，CDM考虑
https://bbs.eetop.cn/thread-917070-1-1.html
(出处: EETOP 创芯网论坛 (原名：电子顶级开发网))

luo7678094

wuzhuoqing 发表于 2021-11-19 16:52
ESD  的HBM，MM，CDM考虑
https://bbs.eetop.cn/thread-917070-1-1.html
(出处: EETOP 创芯网论坛 (原名： ...

copper_hou

楼主的说法与现实还是有出入的。IC的ESD保护设计要求（及趋势）是包括HBM与CDM，而CDM的考虑占比会越来越高，不再考虑MM的设计，更多的还是基于IC在使用阶段（IC封装与测试、SMT、电子产品整机组装等）ESD的主要情形：MM中的设备带静电的金属物体只要接地，就消除了，而且在电子工厂的设备设计与使用维护都会有效应对；依此类推，HBM的设计要求也会逐渐弱化；相比之下，CDM在IC使用阶段（IC封装与测试、SMT、电子产品整机组装等）的占比越来越高（现今基本超过50%），所以，IC的CDM保护设计要求会越发强化。


以下是JEDEC发布（2014年）取消MM作为IC ESD保护设计要求的背景原因：
• MM is redundant to HBM at the device level since it produces the same failure mechanisms, and the two models generally track each other in robustness and in failure modes produced.
• The MM test has more variability and, consequently, less repeatability than HBM due to the MM's greater sensitivity to parasitic effects in the tester circuitry.
• There are no significant engineering studies (with verified data) which could be used to establish a required passing level for MM.
• The test method was incorrectly given the name “machine model”, though no firm, unique connection between the model and actual machine-induced device failures was ever established.
In fact the model was developed as a “low-voltage HBM”.
• CDM does a better job of screening for fast metal-to-metal contact events than MM.
• The vast majority (> 99%) of electrical failures in manufacturing correlate to CDM or to EOS and not to MM.
• MM testing has not shown any additional failures not explained by CDM, HBM or EOS.
• MM testing consumes resources and creates time-to-market delays while providing no additional failure modes or protection strategies which have not been covered by HBM and CDM.