Ion-Injected Alignment Marks for SiC Epitaxial Mask Positioning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for manufacturing power semiconductor devices using silicon carbide substrates face challenges in accurately estimating the coordinates of alignment patterns, leading to decreased accuracy in mask positioning due to the presence of facet surfaces, which affects the epitaxial layer formation and device performance.
Innovation Solution
A semiconductor device and manufacturing method that include a bulk substrate with an epitaxial layer and an alignment region featuring an ion-injected layer, where the ion-injected layer is formed in part of the alignment region to improve the accuracy of mask positioning by altering the crystalline properties and preventing wrong recognition of alignment pattern edges during epitaxial layer formation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If an alignment pattern is formed by recess or protrusion through dry etching, then the alignment pattern can be used for mask positioning, but the facet surfaces cause wrong recognition of alignment pattern edges, decreasing mask positioning accuracy
Solution Approach 1:
The patent changes the physical-chemical state of the alignment pattern by forming an ion-injected layer within the recess or protrusion. This ion injection modifies the crystalline structure and physical properties of the alignment pattern region, creating a distinguishable feature that prevents wrong edge recognition during mask positioning, thereby resolving the accuracy degradation caused by facet surfaces
Solution Approach 2:
The ion-injected layer acts as an intermediary substance within the alignment pattern structure. This intermediate layer with distinct physical properties (such as different etch rate or optical characteristics) serves as a reliable reference feature that mediates between the facet surface interference and the mask positioning system, enabling accurate coordinate estimation despite the presence of facet surfaces
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
This approach enables accurate estimation of alignment pattern coordinates, enhancing mask positioning accuracy and improving the overall quality of semiconductor devices, such as MOSFETs, by preventing errors in epitaxial layer formation and increasing the reliability of device manufacturing.
Implementation Method 1
an ion-injected layer is formed in at least a part of the alignment region
Data Source
AI summary
A semiconductor device includes a bulk substrate, and an epitaxial layer formed on a surface of the bulk substrate. A part of the surface of the bulk substrate is an alignment region including an alignment pattern defined by at least one recess or one protrusion. An ion-injected layer is formed in at least a part of the alignment region.