Stacked HBM Contact Structure for Self-Aligned Die Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor devices face challenges in achieving high memory density, bandwidth, and data transfer speed while maintaining efficient manufacturing processes and reducing costs.
Innovation Solution
The semiconductor device incorporates multiple memory dice stacked vertically with direct bonding technology, utilizing contact structures that extend into the stacked memory dice, allowing for self-alignment and higher interconnection density, and includes a base die for support, reducing the need for carrier wafers and enhancing manufacturing efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If multiple memory dice are stacked vertically to increase memory density, then memory density and capacity increase, but manufacturing complexity and alignment precision requirements increase
Solution Approach 1:
The contact structures are designed to automatically self-align during the stacking process. The protruding portions of contact structures extend into recesses of adjacent memory dice, creating mechanical interlocking that ensures precise alignment without requiring external alignment mechanisms or complex positioning systems.
Solution Approach 2:
The contact structures extend in the vertical dimension (first direction) through the stacked memory dice, rather than only in horizontal planes. This vertical extension allows interconnections to pass through multiple layers, enabling three-dimensional integration and reducing the need for complex lateral routing.
2Productivity
If contact structures extend through multiple stacked memory dice, then interconnection density increases, but manufacturing process complexity increases
Solution Approach 1:
The contact structures are segmented into distinct portions: protruding portions that extend into adjacent memory dice and non-protruding portions that remain within individual dice. This segmentation allows each portion to be optimized independently for its specific function, simplifying the overall manufacturing process.
Solution Approach 2:
Multiple interconnection functions are merged into single integrated contact structures that simultaneously provide electrical connections across multiple memory dice layers. The contact structures combine mechanical support, electrical conduction, and alignment reference functions in one element, reducing the total number of components and manufacturing steps.
3Productivity
If direct bonding technology is used to stack memory dice, then manufacturing efficiency improves, but bonding reliability requirements increase
Solution Approach 1:
The contact structures are pre-formed with protruding portions before the stacking process. This preliminary preparation ensures that when memory dice are bonded together, the contact structures are already positioned to engage with recesses in adjacent dice, eliminating the need for post-bonding alignment operations and ensuring reliable electrical connections.
Solution Approach 2:
The contact structures feature rounded or tapered protruding portions that facilitate easier engagement with recesses during bonding. This geometric design reduces stress concentrations and allows for tolerance compensation, enhancing bonding reliability while maintaining manufacturing efficiency.
Data Source
AI summary
The present disclosure relates methods, devices, systems, and techniques for high bandwidth memory (HBM). An example semiconductor device includes a first layer, a second layer, a first die between the first layer and the second layer, and a second die stacked together along a first direction. Each of the first die and the second die has a conductive layer. The first die and the second die are bonded through the second layer. The semiconductor device further includes a first contact structure coupled to the conductive layer of the first die and a second contact structure coupled to the conductive layer of the second die. The first contact structure extends along the first direction and contacts the conductive layer of the first die without extending through the second layer. The second contact structure extends through the second layer along the first direction without extending through the second die.