METHODS AND APPARATUS FOR SEARCHING FOR DEFECTIVE PATTERN, FOR SEARCHING FOR PATTERN, AND FOR COMPRESSING, RESTORING AND REFERENCING DATA, SEMICONDUCTOR MEMORY TESTER, DEFECTIVE PATTERN SEARCHING SYSTEM AND PRODUCTION MONITOR

摘要

PROBLEM TO BE SOLVED: To search for a user-designated arbitrary-shaped detective pattern without deciding and developing test result data compressed in a memory, by compressing data, using a compression system capable of perfectly decoding the data in original data and referencing the data being compressed at arbitrary positions. SOLUTION: Data of test results about all data in a semiconductor memory describing whether each of the cells of a semiconductor memory is food or not are compressed by a method capable of perfectly decoding the data into original data and referencing the data being compressed at arbitrary positions. If required, the compressed data are decoded into the original data. The data being compressed at arbitrary positions are reference among the compressed data. The pattern search is made, using a pattern searching system capable of searching for a pattern of an arbitrary shape among the data under search, without referencing all the data existing in the compressed data under search.