Research On Modeling And Fault Test Method Of Signal Integrity Of Complex Interconnect Structure

With the rapid development of integrated circuit design technology and improvement of electronics technology, varieties of new technologies are used in development and design of electronic systems. At the same time, signal integrity problems in high-speed circuit interconnect structure are increasingly serious, especially for complex interconnect structure included via holes, solder balls and traces. As a whole transmission path, via holes and solder balls have discontinuities and parasitic effects which will affect the signal transmission quality. Mechanical process failures may arise in assembly and production processes will seriously affect signal propagation quality. Therefore, the research on the signal integrity issue modeling analysis and fault diagnosis method of complex interconnect structure constituted by via holes, solder balls and traces in high speed circuit is very necessary. For the problems of signal integrity in high speed circuit complex interconnect structure this paper mainly does the following work:1. According to the related theory of the signal integrity, the reflection and crosstalk problems are emphatically analyzed.2. The electromagnetic modeling for complex interconnect structure by via holes, solder balls and traces is established. The return loss and the next crosstalk of the complex interconnect structure are simulated. Comparative to the simulation results of different parameters, The simulation results show that discontinuous type are the main factors affecting the return loss, coupling interval and the coupling length is a decisive factor in the next crosstalk.3. Based on the theory of signal integrity such as the transmission line theory, high speed circuit theory etc, the equivalent circuit model of complex interconnect structure by via holes, solder balls and traces is put forward, and the circuit model was validated by circuit simulation.4. Fault tests for dual path complex interconnect structure is explored, and the method of fault voltage detection is performed. Verification of via hole crack failure and solder ball void failure are carried out, and the advantages and disadvantages are distinguish. The results show that the method can effectively diagnose for small fault.