TO-CAN Laser Reducing Parasitic Inductance via Conductive Sheets
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current TO-CAN packaging technology is inadequate for high-speed applications exceeding 25 Gb/s, as it results in longer wire bonding distances that negatively impact signal transmission due to increased parasitic inductance and resistance, making it difficult to achieve high-frequency performance.
Innovation Solution
A TO-CAN packaged laser design that includes a substrate with conductive sheets and a laser chip, where the anode and cathode are electrically coupled with pins protruding from the base using conductive welding flux or paste, reducing wire bonding distance and facilitating signal transmission by allowing direct contact between the pins and conductive sheets.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional TO-CAN packaging technology is used, then the packaging structure is simple and easy to manufacture, but the wire bonding distance is long which increases parasitic inductance and resistance, making it difficult to achieve high-speed transmission rates above 25 Gb/s
Solution Approach 1:
The patent introduces a three-dimensional packaging structure where the laser chip is mounted vertically on the substrate at an position close to the pins, rather than the traditional planar arrangement. This spatial reconfiguration dramatically shortens the wire bonding distance from the millimeter range to the micrometer range, reducing parasitic inductance and enabling high-speed transmission above 25 Gb/s while maintaining TO-CAN packaging simplicity
2Speed
If the wire bonding distance is shortened to reduce parasitic inductance, then high-speed signal transmission above 25 Gb/s can be achieved, but the positioning precision and manufacturing complexity increase
Solution Approach 1:
The patent employs preliminary positioning structures including precision mounting holes and alignment features on the substrate that guide the laser chip placement. The conductive sheets are pre-positioned and connected to pins before chip mounting, ensuring that when the laser chip is installed, the wire bonding distance is automatically minimized without requiring complex post-assembly adjustments or high-precision positioning equipment
Solution Approach 2:
The substrate serves as an intermediary component that integrates multiple functions: it provides mechanical support, electrical connections through conductive sheets, and precise positioning features. The conductive sheets act as intermediaries between the pins and the laser chip electrodes, enabling short wire bonds while simplifying the manufacturing process by allowing standard bonding equipment to be used
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 design shortens the wire bonding distance, reduces parasitic inductance, and enhances high-speed signal transmission quality by enabling closer proximity of high-speed pins to the laser chip, thus improving the performance of high-frequency devices.
Implementation Method 1
the first pin is coupled with the first conductive sheet by conductive welding flux or conductive paste and the second pin is coupled with the second conductive sheet by conductive welding flux or conductive paste
Data Source
AI summary
The present disclosure provides a TO-CAN packaged laser and an optical module. According to an example, the TO-CAN packaged laser includes a base; a substrate located on the base, where the substrate is provided with a first conductive sheet and a second conductive sheet; a laser chip provided on the substrate, where an anode of the laser chip is electrically coupled with the first conductive sheet and a cathode of the laser chip is electrically coupled with the second conductive sheet; and a first pin and a second pin that protrude from the base, where the first pin is coupled with the first conductive sheet by conductive welding flux or conductive paste and the second pin is coupled with the second conductive sheet by conductive welding flux or conductive paste.