A high-speed, long-reach signal design challenge for 2.5-D LSI based on a low-cost silicon interposer and a large-scale SSO analysis

A new signal line structure based on a single-sided low-cost silicon interposer is proposed, which extends high-speed signal reaching distance over 16 mm. The proposed signal structure and design scheme are applied to a full-function 2.5-D LSI product that has originally been developed based on a wide-pin pitch organic substrate. Despite a long signal length, the fabricated LSI has successfully worked with a large enough operation margin. This paper also discusses an SSO model reduction technique that enables the analysis of hundreds of parallel signal lines in a practical period. The design method presented in this paper can further extend the range of the low-cost silicon interposer application beyond the usage for wide-I/O or HBM (high bandwidth memory).