The Design And Fabrication Technology Of MEMS Cantilever Probe Card

Wafer-level IC test probe card is mainly used in the test of chip's electric characters before packaging. With the increase of the chip complexity, and the great improvement of operation speed, traditional probe card can't work properly because of the influence of the parasitic capacity and inductance, what's more , the density of tips of traditional probe card is limited. So, in this paper, a novel micro mechanical probe card with aluminum-via and self-alignment technology was introduced. This kind of probe card consists of an array of tips which are at the bottom of special designed cantilevers. In our paper, the design method of the probe card structure is discussed in details and the special fabrication process is provided, the arrangement of the tips of the probe card is based on the actual positions of the pads of the DUT. The test result shows that the resistance of the probe card is below 1 Ω.The history of MEMS technology, categories of MEMS devices and some typical MEMS devices are introduced in chapter 1, The development of MEMS probe card is also introduced, What's more, the advantages and disadvantages of various kinds of probe cards are discussed.In chapter2, the mechanical equations that the cantilever of probe card must abbey are conducted. From those equations, the dimensions of the cantilevers are gotten. The simulation results with Ansys are given too.In chapter3, some experiments are conducted to get the key parameters of the fabrication process, at the same time, the feasibility of the process is proved.In chapter4, the whole fabrication process, experiment results and some SEM photos are given. At last, the resistance of the probe card is measured, and the results meet our request well. Chapter5 concludes all the jobs I have done.