摘要
目前国际电工组织(IEC)及美军发布的标准中集成电路、混合集成电路及半导体分立器件均基于批次允许不合格率(LTPD)进行抽样,一般控制使用方风险为10%。这些标准将元器件缺陷样本数限制在25个,若超过则没法判定批次是否合格。根据美军标中抽样方案中缺陷数小于等于1时,对生产方来说风险太大,而缺陷数大于等于10时,对生产方风险接近零。元器件筛选一般为100%进行检测,其批次样本量与标准中最小样本量往往有出入。目前航空领域二次筛选规范规定的元器件允许不合格率(PDA)要求一般为15%,国内元器件很多厂家对PDA理解有偏差,将批次缺陷比例的观测值与PDA要求值直接进行比较,进一步放宽了要求。针对以上问题将美军标及国军标中的抽样方案进行了修正,提出了基于泊松分布的双方风险均等的筛选方案,并给出了涵盖所有缺陷数的合格判据。
The current standards of IEC and USA military for IC(Integrated Circuit),hybrid IC and discrete semiconductor components are all based on LTPD(Lot Tolerance percent Defective),the sampling plan is determined by controlling the consumer’s 10%.These standards limit the number of component defective samples to 25,beyond which it is impossible to determine whether a lot is acceptable.When the number of defectives is less than or equal to 1,the risk is too large for the producer,while the number of defectives is bigger than or equal to 10,the risk is close to zero for the producer.Components screening is usually performed at 100%,the lot sample size is often different from the minimum sample size in the standard.At present,the requirement of PDA(Percent Defective Allowable)in the second screen specification in aviation field is 15%.The domestic components manufacturers generally have deviation in the understanding of PDA,and directly compare the observed value of lot defect proportion with the PDA requirement value,the requirements have been further loose.In order to solve the above problems,modifies the sampling plan in USA military standard and GJB,puts forward a screening plan based on Poisson distribution and gives the acceptable criterion of PD observation which covers all defectives.
作者
王道震
赵明
徐建生
刘红波
徐琼琼
高建秀
WANG Dao-zhen;ZHAO Ming;XU Ji an-sheng;LIU Hong-bo;XU Qiong-qiong;GAO Jian-xiu(Tianjin 712 Communication&broadcasting Co.,Itd.,Tianjin 300462;China Helicopter Design and Research Institute,Tianjin 300300)
出处
《环境技术》
2023年第1期144-148,共5页
Environmental Technology
