Ceramic Wiring Substrate Groove Design for Reliable Separation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for producing ceramic wiring substrates often result in damaged plating films and brazing material layers due to acute-angled dividing grooves, leading to accidental fusion of brazing material layers and difficulties in separating individual substrates without causing damage.
Innovation Solution
The use of deep groove portions with obtuse-angled cross sections and shallow groove portions with horizontal ceramic surfaces on both sides of the openings, formed through a two-step laser irradiation process, prevents damage to plating films and brazing material layers during substrate separation and ensures reliable separation of individual wiring substrates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a blade is used to form dividing grooves in green sheet laminate, then burrs are reduced in the vicinity of dividing grooves, but the grooves have a V-shaped cross section that causes accidental fusion of brazing material layers and damage to plating films during valley folding
Solution Approach 1:
The dividing groove is segmented into two distinct parts: a deep groove portion formed by first laser irradiation and a shallow groove portion with horizontal surfaces formed by second laser irradiation. This segmentation allows each portion to serve a specific function - the deep groove provides separation while the shallow groove with horizontal surfaces prevents friction and damage during valley folding operations.
Solution Approach 2:
The mechanical blade cutting process is replaced with a two-step laser irradiation process. The first laser forms the deep groove portion and the second laser forms the shallow groove portion with horizontal surfaces. This substitution eliminates the V-shaped cross-section problem inherent in blade cutting while maintaining burr reduction benefits.
2Manufacturing precision
If a two-step laser irradiation process is used to form deep and steep narrow portions with chamfered openings, then dividing grooves with Y-shaped cross section are created, but plating films and brazing material layers are still damaged due to friction during valley folding
Solution Approach 1:
The groove structure is designed with different local qualities: the deep groove portion has steep walls for effective separation, while the shallow groove portion has horizontal surfaces that provide a low-friction interface during valley folding. This local differentiation of groove characteristics prevents damage to plating films and brazing material layers while maintaining manufacturing precision.
3Productivity
If V-shaped dividing grooves are formed, then production efficiency is maintained, but sufficient groove width is not provided between adjacent wiring substrates preventing reliable separation
Solution Approach 1:
The groove design transitions from a single-dimensional V-shaped cross-section to a two-dimensional structure with both depth and horizontal surface components. The shallow groove portion with horizontal surfaces extends the effective groove width at the opening level, providing sufficient separation between adjacent substrates while maintaining the efficiency benefits of the deep groove portion.
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 prevents damage to plating films and brazing material layers, avoids accidental fusion of brazing material layers, and allows for reliable separation of individual substrates while ensuring secure bonding of metallic lid plates or fittings to cavities, thereby enhancing the production of multi-piece wiring substrate arrays.
Implementation Method 1
forming deep groove portions 28 having cross-sectional obtuse angles θ and shallow groove portions 29 having horizontal surfaces 27 on both sides of openings thereof by irradiating a laser beam L a plurality of times
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
Provided are a wiring substrate including a substrate main body and a metalized layer provided on the front surface of the substrate main body so as to extend along side surfaces thereof, in which a plating film and a brazing material layer covering the surface of the metalized layer are not damaged; a multi-piece wiring substrate array for simultaneously providing a plurality of the wiring substrates; and a method for producing the multi-piece wiring substrate array. The wiring substrate 1a includes a substrate main body 2 which is formed of a ceramic laminate S and has a rectangular shape in plan view, and which has a front surface 3 and a back surface 4 and has four side surfaces 5, each being located between the front surface 3 and the back surface 4, and having a groove surface 7 located on a side toward the front surface 3 and a fracture surface 6 located on a side toward the back surface 4; and a metalized layer 11 which is formed on the front surface 3 of the substrate main body 2 so as to extend along the four side surfaces 5, and which has a rectangular frame shape in plan view, wherein a horizontal surface 13 of the ceramic laminate S of the substrate main body 2 is exposed between the metalized layer 11 and the groove surface 7 of each side surface 5 of the substrate main body 2.