Semiconductor Package Sealing Without Grinding for Electrode Exposure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing manufacturing methods for semiconductor devices using SiC MOSFETs face issues with dust generation and moisture ingress during grinding, material wastage due to electrode height variations, and increased machining costs, making it difficult to reliably expose electrode members without increasing manufacturing costs.
Innovation Solution
A method involving bonding semiconductor and wiring chips to a substrate, using buffer materials to ensure electrode members are pressed against a mold, allowing for non-grinding sealing with a sealing material that fills gaps, thus exposing electrode members without additional machining costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the sealing material is ground to expose electrode members, then the electrode members can be reliably exposed from the sealing material, but dust is generated, moisture enters from the ground surface, and machining cost increases
Solution Approach 1:
The electrode members are positioned and fixed at predetermined heights before the sealing material is applied. The buffer material is placed in advance to ensure that the electrode members protrude from the sealing material surface without requiring subsequent grinding operations. This preliminary positioning eliminates the need for post-sealing machining.
Solution Approach 2:
The grinding process is completely removed from the manufacturing workflow. Instead of applying sealing material and then grinding it away to expose electrodes, the method extracts the grinding step entirely by using buffer material to pre-establish the correct electrode exposure height, thereby eliminating dust generation and machining costs.
2Manufacturing precision
If the sealing material is ground to expose electrode members, then the electrode members can be exposed, but electrode members are ground more than necessary due to height variations, causing material wastage and extended machining period
Solution Approach 1:
The buffer material is placed before applying the sealing material to pre-determine the exposure height of electrode members. This preliminary action ensures that electrode members of varying heights will all protrude appropriately without requiring excessive sealing material that would later need to be ground away.
Solution Approach 2:
The method changes the height parameter control approach from post-processing (grinding) to pre-processing (buffer material positioning). By controlling the buffer material thickness and positioning, the system accommodates height variations in electrode members without material wastage.
3Manufacturing precision
If the sealing material is ground to expose electrode members, then the electrode members can be exposed, but machining cost and time increase
Solution Approach 1:
The grinding operation is completely extracted from the manufacturing process. The method replaces the multi-step process of sealing followed by grinding with a single sealing step using buffer material, thereby eliminating machining time and improving productivity.
Solution Approach 2:
The buffer material is positioned in advance to ensure proper electrode exposure, eliminating the need for subsequent machining operations. This preliminary action streamlines the process by ensuring correct positioning before sealing, thereby improving manufacturing efficiency.
Data Source
AI summary
A semiconductor chip including a main electrode and a control electrode is bonded to a substrate. A wiring chip including a first electrode, a second electrode and a wiring is bonded to the substrate. A main electrode member is bonded to the main electrode. A control electrode member is bonded to the second electrode. The control electrode is bonded to the first electrode with a connection member. The semiconductor chip, the substrate, the wiring chip, the main electrode member, the control electrode member and the connection member are putted into a mold and are sealed with sealing material by injecting the sealing material into the mold in a state that distal end surfaces of the main electrode member and the control electrode member are pressed against a buffer material provided between the main electrode member/the control electrode member and the mold. The sealing material is not ground.