Semiconductor Die Clip Layout With Under-Clip Wire Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The reduction in size of semiconductor dies due to advancements in semiconductor technology limits the space available for soldering or sintering clips, which in turn reduces the area for top-side cooling of the package, especially when accommodating gate bond wires or current sense bond wires.
Innovation Solution
A semiconductor device design that includes a semiconductor die with contact pads on both main faces, a clip connected to one of the contact pads, and a wire disposed at least partially under the clip, with an insulation layer or insulator body to prevent electrical contact between the wire and the clip, allowing for a larger clip to be placed over the die for efficient dual-side cooling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of moving object
If the semiconductor die size is reduced to improve integration density, then the area available for soldering or sintering a clip is reduced, but this limits the clip size and reduces the area for top side cooling
Solution Approach 1:
The patent moves the bond wire from the top surface to the bottom surface of the clip, utilizing the third dimension (depth/height) to resolve the space conflict. This allows the clip to maintain a large top surface area for cooling while accommodating the wire routing through the clip's thickness, effectively adding a vertical dimension to the wire path.
Solution Approach 2:
The bond wire is disposed partially under the clip, nesting the wire within the vertical space occupied by the clip structure. This nesting arrangement allows the wire to be contained within the clip's footprint without requiring additional top surface area, thus preserving cooling area while maintaining electrical connectivity.
2Temperature
If a large clip is placed over the die for efficient dual-side cooling, then thermal management is improved, but the bond wire may form an electrical contact with the clip causing a short-circuit
Solution Approach 1:
An insulator body is introduced as an intermediary element between the bond wire and the clip. This insulator prevents direct electrical contact between the wire and the conductive clip, eliminating the short-circuit risk while allowing the wire to remain positioned under the clip for thermal management purposes.
Solution Approach 2:
The insulator body is positioned in advance at the location where the wire will pass under the clip. This preliminary placement of the insulator ensures that when the wire is subsequently positioned, electrical isolation is already in place, preventing any potential short-circuit before the device is fully assembled.
3Ease of manufacture
If the clip size is reduced to accommodate gate bond wire or current sense bond wire, then wire routing is simplified, but the area for top side cooling is reduced
Solution Approach 1:
Instead of reducing the clip's top surface area to create wire routing space, the patent utilizes the vertical dimension by positioning the wire under the clip. This maintains the full top surface area for cooling while providing adequate space for wire routing through the clip's thickness.
Solution Approach 2:
The patent creates a simplified model of wire routing where the wire follows the contour of the clip's bottom surface. This copying of the clip's geometry for wire placement simplifies the manufacturing process while maintaining full cooling area, as the wire naturally conforms to the available space under the clip.
Data Source
AI summary
A semiconductor device includes a first carrier, a first external contact, a second external contact, and a first semiconductor die. The first semiconductor die has a first main face, a second main face opposite to the first main face, a first contact pad disposed on the first main face, a second contact pad disposed on the second main face, a third contact pad disposed on the second main face, and a vertical transistor. The first semiconductor die is disposed with the first main face on the first carrier. A clip connects the second contact pad and the second external contact. A first wire is connected with the first external contact. The first wire is disposed at least partially under the clip.