High Temperature Sensor Package Flip-Chip Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for packaging electronic components, such as leadframes and PCBs, face challenges including high costs, limited flexibility, and inefficiencies in connecting sensors to input/output devices, especially for high-temperature applications where materials like gold and tin are inadequate, and existing bonding techniques like wire bonding and soldering are not cost-effective or durable.
Innovation Solution
The use of Flip-Chip On Board (FCOB) technology with a plastic substrate and ultrasonic bonding techniques to create a sensor package apparatus that includes a silicon carbide die, a metallization layer, and a leadframe connected via laser welding, allowing for robust and compact electrical and physical connections capable of operating in high-temperature environments.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If leadframes are used for connecting sensors to input/output devices, then electrical connections can be established, but manufacturing costs increase and manufacturing complexity increases
Solution Approach 1:
The patent extracts the leadframe from the packaging structure and replaces it with direct wire bonding from the die to the ceramic substrate. This eliminates the need for leadframe stamping, plating, and assembly operations, thereby reducing manufacturing costs while maintaining electrical connection reliability through direct bonding.
Solution Approach 2:
The ceramic substrate serves multiple functions: it provides mechanical support, electrical insulation, and electrical connection pathways. By integrating these functions into the substrate rather than requiring separate leadframe components, the patent reduces overall manufacturing complexity and cost while maintaining reliable electrical connections.
2Reliability
If leadframes are used for connecting sensors to input/output devices, then electrical connections can be established, but device complexity increases
Solution Approach 1:
The patent removes the leadframe component entirely from the packaging structure, replacing it with direct wire bonding techniques. This extraction simplifies the overall device structure by eliminating multiple components (leadframe, insulation, plating layers) while maintaining reliable electrical connections through direct die-to-substrate bonding.
3Reliability
If traditional wire bonding or soldering techniques are used, then electrical connections can be made, but the bonding strength decreases at high temperatures
Solution Approach 1:
The patent changes the bonding parameters by using eutectic bonding at elevated temperatures (approximately 480°C for Au-Sn) to create strong metallurgical bonds. This parameter change enables the formation of intermetallic compounds that provide superior bonding strength and high-temperature reliability compared to traditional wire bonding or soldering techniques.
Solution Approach 2:
The patent employs composite material systems including Au-Sn eutectic alloys, Pt-Rh thermocouple materials, and various metallization layers (Ti, Pd, Pt, Au, Sn) on the ceramic substrate. These composite material combinations provide both strong bonding at bonding temperatures and stable performance at high operating temperatures, resolving the contradiction between bonding strength and temperature resistance.
4Reliability
If gold plating is used for wire bonding, then electrical connections can be made, but manufacturing costs increase
Solution Approach 1:
The patent applies local quality by providing metallization only where needed on the ceramic substrate - specifically at the bonding pads and interconnect regions. Rather than plating the entire leadframe or substrate, the metallization (Ti, Pd, Pt, Au, or Sn layers) is applied locally to create reliable bonding surfaces, reducing material costs while maintaining electrical connection quality.
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 reduces manufacturing costs, enhances packaging density, and enables reliable operation from 600° C to 1000° C and above, overcoming the limitations of traditional bonding methods by providing a cost-effective and efficient solution for high-temperature sensor applications.
Implementation Method 1
ultrasonic bonding techniques to create a sensor package apparatus that includes a silicon carbide die, a metallization layer, and a leadframe connected via laser welding
Implementation Method 2
a leadframe connected via laser welding, allowing for robust and compact electrical and physical connections capable of operating in high-temperature environments
Data Source
AI summary
A sensor package apparatus and method are disclosed in which a sensor die is provided and based on a substrate. An integrated circuit is generally associated with the sensor die. A leadframe is also provided, which is connected by at least one weld to the integrated circuit and the substrate. The integrated circuit, the leadframe, and the sensor die are configured in a flip-chip arrangement to protect the sensor die and form a sensor package apparatus that provides compact and robust electrical and physical connections thereof. The integrated circuit can be formed from, for example, silicon carbide. A metallization layer can also be formed on the integrated circuit, wherein the integrated circuit is configured upon the substrate of the sensor die. The metallization layer thus adheres to the integrated circuit via the weld(s).