关键词: 2.5D, 转接板, 熔丝, 故障覆盖率

Abstract:

Pre-bond testing of interposers has an important impact on the yield of 2.5D integrated circuits. To improve the fault coverage of interposers and reduce the test cost, a new technique for testing the open-fault and short-fault on the interconnect wires is proposed, which only employs one auxiliary interposer. The presented technique firstly divides the interconnect wires into several groups by the algorithm which can find the largest independent set in an adjacency matrix. The interconnect wires within one group will not generate short faults. After grouping, the wires are added on the auxiliary interposer to connect the intra-group wires. Then e-fuse is added on the auxiliary interposer via the presented the e-fuse connection strategy to connect inter-group wires. The presented connection strategy of inter-group e-fuse can maximize the number of parallel test loops and minimize the number of required e-fuse. During the test, the open-fault testing is firstly performed. After the open-fault test, the e-fuse on the auxiliary interposer will be blown and the short-fault testing will be conducted. Experimental results show that the proposed technique can effectively increase the open-fault and short-fault coverage, and reduce the hardware cost.

Key words: 2.5D, silicon interposer, e-fuse, fault coverage