Study Of Reliability Testing Of GaAs PHEMT

Gallium arsenide(Ga As) is compound semiconductor. Some electronic properties of gallium arsenide are superior to silicon. It has higher saturated electron velocity and higher electron mobility, allowing GaAs device to function at higher frequencies and higher power. As a wide direct band gap material with resulting resistance to radiation damage, GaAs is an excellent material for satellite communication, space technology, and military industrial technology. With long period developing,GaAs chip grew up from single transistor to complex MMIC(MMIC: Monolithic Microwave Integrated Circuit). Until now the major process for MMIC is pHEMT( Pseudomorphic HEMT). The pHEMT process used many materials, equipment and process module, all these factors will influent the product reliability, This paper described the basic by step pHEMT process, the materials used in every step, how the process and materials affect the product reliability and some possible solution. Introduced some basic concept for reliability, Then selected some proper test items for GaAs pHEMT process and MMIC product base on the industry standard and experience, introduced and discussed the related scope, test method and test structure. Designed the general reliability test structure base on the pHEMT process design rule. and related standard..In order to improve the reliability test efficiency, Grouped the pHEMT reliability test as process reliability and product reliability, and set the reliability test flow for different purpose and scope for reliability test control. Did accelerate life time test for pHEMT active device with existing test system, and calculated the device life time, the value was acceptable. As the test system function is poor and low through put, Analyzed the accelerate life time test system function request and trend, provided the feasible solution for the system update, list the detail hardware solution.