3D IC Circuit Routing Using Projected Inter-FSR Nets

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The increasing size and complexity of integrated circuit (IC) designs lead to longer implementation times and reduced routability, with conventional routing techniques struggling to generate feasible solutions efficiently, particularly due to inter-FSR nets that compete for routing resources.

Innovation Solution

The method involves detecting inter-FSR nets in 3D IC devices, projecting their sources and anchors to a reserved die, transforming them into modified inter-FSR nets coupled with intra-FSR nets, and routing these nets in parallel with intra-FSR nets, using distinct routing resources.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If conventional routing techniques are used for larger circuit designs, then the routing process is simpler to implement, but the runtime increases and routability decreases

Engineering Contradiction:

Improverouting implementation simplicityVSAvoidrouting runtime and feasibility

Core Design Contradiction:

Ease of manufactureVSProductivity

Solution Approach 1:

The patent segments the routing problem by dividing the circuit design into multiple dies, each with multiple fabric sub-regions (FSRs). Routing is performed independently within each FSR, and inter-FSR connections are handled through projected anchors on a reserved die. This segmentation transforms the monolithic routing problem into multiple smaller, manageable sub-problems, improving both runtime and feasibility.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent introduces a reserved die as an intermediary structure that receives projected anchors from multiple other dies. This intermediary resolves the complexity of inter-die routing by providing a centralized projection mechanism that simplifies connection establishment between FSRs across different dies, thereby improving routing feasibility and reducing runtime.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Ease of operation

If inter-FSR nets are routed using conventional methods, then the routing process is straightforward, but the competition for routing resources reduces feasibility

Engineering Contradiction:

Improverouting process simplicityVSAvoidrouting feasibility

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The patent resolves resource competition by transitioning from a two-dimensional routing approach to a three-dimensional solution space. Multiple FSRs are projected onto a reserved die in the vertical dimension, allowing inter-FSR nets to be routed through the Z-axis dimension. This dimensional transformation provides additional routing paths that avoid direct competition for planar routing resources, thereby improving feasibility without complicating the routing process.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Data Source

PatentUS20260044661A1Circuit design implementation for 3-dimensional integrated circuit devices

Publication Date: 2026.02.12 XILINX INC

AI summary

Implementing a circuit design for an integrated circuit device having a plurality of dies where each die has a plurality of fabric sub-regions (FSRs) includes detecting an inter-FSR net of the circuit design. A source of the inter-FSR net and an anchor for the inter-FSR net are projected to a selected die of the plurality of dies resulting in a projected source and a projected anchor in the selected die. The inter-FSR net is replaced with a modified inter-FSR net coupling the projected source with the projected anchor in the selected die and a new intra-FSR net coupling the anchor with a load of the inter-FSR net. The circuit design including the modified inter-FSR net and the new intra-FSR net is routed.