A Low-Loss Edge-Coupled Signal Transmission Between Chiplets in Sub-THz by a TSV-Surrounded Structure
Journal
IEEE Transactions on Microwave Theory and Techniques
Start Page
1-12
ISSN
0018-9480
1557-9670
Date Issued
2025
Author(s)
Abstract
This article introduces a novel edge-coupled structure for achieving low-loss sub-terahertz signal transmission between chiplets. The proposed structure enables direct signal transmission between two chiplets without passing through the interposer, microbumps, and traces on the interposer in conventional conducting interconnects. Based on the theory of coupled lines, analytical design equations are presented. The challenges of imperfect chiplet assembly are also considered during the design procedures. The proposed low-loss edge coupler is designed and fabricated using the integrated passive device (IPD) process. To prevent coupled signals from leaking into the air gap between chiplets, through substrate vias (TSVs) are strategically positioned around the coupler. Additionally, the IPD chips with edge couplers are mounted on printed circuit boards (PCBs) to demonstrate the feasibility of applying the proposed design to chiplets for sub-terahertz system-in-package (SiP) integration. The proposed design can achieve a chip-to-chip insertion loss of 1.23 dB at 150 GHz, validating the low-loss property of the proposed edge-coupled structure.
Publisher
Institute of Electrical and Electronics Engineers (IEEE)
Type
journal article