Recessed III-V Semiconductor Structure for Crack-Free Dicing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge in semiconductor manufacturing lies in efficiently singulating semiconductor devices with direct bandgap materials like group III-V compounds without introducing cracks or delamination due to lattice mismatch between the substrate and the group III-V layer, which affects yield and manufacturing costs.
Innovation Solution
A semiconductor structure is developed with a substrate, a group III-V layer, and a dielectric layer, featuring a recess with inclined sidewalls and a passivation layer that covers the interface between the substrate and the group III-V layer, allowing for precise cutting and reducing the risk of cracks or delamination during the singulation process. This structure includes a two-step photolithography process to ensure accurate patterning and coverage of the recess, enabling efficient manufacturing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional singulation methods are used on group III-V semiconductor devices, then manufacturing efficiency is maintained, but cracks and delamination occur due to lattice mismatch between substrate and group III-V layer
Solution Approach 1:
The patent applies preliminary action by forming recesses in the substrate before depositing the group III-V layer. This pre-structured substrate geometry allows subsequent singulation to occur along predetermined paths that avoid the group III-V layer, preventing cracks and delamination while maintaining manufacturing efficiency. The recesses are created as a preliminary step that facilitates safe cutting operations later in the process.
Solution Approach 2:
The substrate is segmented by forming recesses that create distinct regions. These recesses divide the substrate into separable sections with exposed group III-V layer surfaces, enabling precise singulation along the recess boundaries. This segmentation approach allows the substrate to be divided into individual devices without compromising the integrity of the group III-V layer during the cutting process.
2Reliability
If recesses are formed to protect the group III-V layer interface, then crack and delamination risk is reduced, but additional manufacturing steps are required
Solution Approach 1:
The patent merges the recess formation step with the existing substrate preparation process flow. By integrating the recess creation into the standard fabrication sequence—performing it after substrate preparation but before group III-V layer deposition—the additional complexity is minimized. The recesses are formed using standard semiconductor processing techniques that are already part of the manufacturing toolkit, reducing the need for specialized equipment or processes.
3Ease of manufacture
If the substrate surface is left rough for cost reasons, then manufacturing costs are reduced, but singulation accuracy deteriorates
Solution Approach 1:
The patent applies local quality by creating smooth, precisely defined surfaces only at the recess regions where singulation occurs. The bulk substrate can maintain a rougher, lower-cost surface finish, while the critical cutting interfaces at the recess boundaries have high precision. This localized approach to surface quality ensures cutting accuracy where needed without incurring the cost of polishing the entire substrate surface.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The proposed solution improves the yield and reduces manufacturing costs by minimizing cracks and delamination, allowing for more accurate and efficient singulation of semiconductor devices while protecting the interface between the substrate and the group III-V layer.
Implementation Method 1
performing a first photolithography process and a second photolithography process on the photoresist layer
Data Source
AI summary
The present disclosure provides a semiconductor device and a fabrication method thereof. The semiconductor device includes a substrate, a group III-V layer disposed on the substrate, a dielectric layer disposed on the group III-V layer, and an inclined sidewall extending from the dielectric layer to the substrate. Wherein the substrate comprising a relative rough surface opposite the inclined sidewall.