The Related Technologies Research Of IC Electro-optic Tester

With the rapid development of the electronics industry, semiconductor processtechnology become mature, the performance of chip is getting better and better, thedegrees of thier integration and complexity have also continued to increase. This hasbrought great challenges to the field of IC testing. As an essential part of ICdevelopment process, IC testing plays a vital role in chip design, production, andapplication process. It almost runs through all the parts of the chips production, fromthe wafer to the finished application. According the testing purposes, the type ofintegrated circuit testing techniques can be divided into the internal test, packagetesting, aging testing and factory quality control testing. Inside these, the internal testtechnology is the key step in chip production, which is mainly used to verify therational design, shorten research time, ensure the chip performance, and reduce designcosts. Comparing with the other types of testing techniques which rely on specialelectronic equipment and computer software, the chip internal test technologyprimarily depended on photoelectric detection. Such as optical emission samplingtechniques, the photoconductive switch sampling. IC electro-optical testingresearched in our study is one of the methods which use laser to detect the IC. Itsprinciple is based on special physical effects of certain materials. Through thesematerials, the laser through them would be modulated by the electrical signal in thechip’s internal interconnect line. With external instruments, we could detect thisoptical change, and then we could calculate the value of the electrical signals in turn,to achieve the purpose of IC testing. This testing technology with its non-intrusive,high-resolution and high sensitivity has got extensive attention by scientists. Atpresent, its research mainly focused on the materials selected, the raise of spatialresolution and the construction of the entire instrumentation system. The paper mainlyfocuses on the practical IC electro-optical testing system. For DC-ray testing systembuilt by ourselves, we study the way to convert optical signal to electrical signals.Also the signal amplification, filtering. According the actual needs, we use virtual instrument technology to set up a practice of self-measurement and data acquisitionsystem. The specific study includes:First of all, we reviewed the developments of electro-optic testing technology inrecent years. On a few key points (material, resolution, and instrumentation), we madedetailed description. Also we introduced the advantages of the DC optical test systemwe used, illustrated the test system we built.Second, according the optical signal obtained by the optical part of our DCoptical test system, we used the photodiode to covert it into electrical signal. Weintroduced characteristics and equivalent model of the photodiode, constructed thecorresponding preamplifier and the post-level voltage amplifier. Then we introducedthe noise sources and characteristics of the preamplifier, analyzed its bandwidth andstability.Again, in order to meet the actual needs, we are no longer using filter with fixedparameters for signal filtering. Instead we use a digital filter. As its parameters canbe programmed to set the filter’s characteristics, we put forward two ways to designsmart filter which can automatically track the input signal frequency to change thecenter frequency. The design process and experimental results are showed in thepaper.Finally, in order to facilitate the testing and analysis, we use Labview, steppermotor, serial and ADC to build a set of two-dimensional electric field signalmeasurement and data acquisition system. We assembled all discrete modules wedesigned, carried on the actual measurement on micro-metal line we made. Thecorresponding experimental data show that our system can act well.So in summary, the entire system we built can basically complete the convert oflight-electrical signal, realizing amplifying, filtering, and acquisition functions. Thesystem will play a guiding role for the IC electro-optical testing.