During the Summer of 2023, I interned at Kelvin Thermal, creators of one of the thinnest and most flexible phase-change cooling solutions.
As a manufacturing engineering intern, I contributed to the production of ultra-thin vapor chambers. Over the 12-week internship, I gained hands-on experience with the design lifecycle, participating in nearly every stage of vapor chamber production.
The TGPs consist of a liquid and vapor substrate that undergo a series of production stages, including surface treatment and plasma processing, to prepare them for thermal bonding processes. Pictures of these stages are shown on the right.
Background
A Kelvin Thermal TGP (Thermal Ground Plane) is a thin vapor chamber, essentially a 2D flat heat pipe, fabricated using flexible printed circuit (FPC)-compatible processes. It offers several advantages:
Low Cost
Ultra-Thin (0.15-0.25 mm thick)
Extremely Light (0.05-0.15 g/cm²)
Flexible (Bending radius between 10-3 mm)
High Thermal Conductivity (Ranges from 4,000 to 25,000 W/mK)
Unprocessed Vapor and Liquid Substrates, Respectively
The vapor and liquid substrates are first bonded to their respective casings, then bonded to each other to form a vapor chamber. This chamber is filled with a heat-transfer liquid, such as water. The liquid substrate contains tiny 'pillars' that create effective flow channels within a specified range. As heat is transferred, the water evaporates and moves to the vapor substrate, carrying the heat away. The vapor then condenses back into water through a wicking structure, allowing the cycle to repeat.
My Contributions
I was involved in nearly all stages of TGP production, from general manufacturing to quality control. My specific contributions included:
Process Development: I worked alongside a mentor to support the development of an assembly line and identify opportunities for process optimization.
Quality Control Activities: I assisted with quality control inspections throughout each stage of production.
High-Volume Manufacturing: I successfully produced a high volume of vapor chambers each week, utilizing plasma processing and thermal cycling techniques.
Teamwork with Interns: I collaborated with a diverse group of interns with various backgrounds and skill sets.
Bonded Liquid and Vapor Substrate Casings
While there is much more I could share about this experience, many details are confidential. Overall, this internship allowed me to apply key manufacturing principles and translate my coursework into a practical setting. I had the opportunity to contribute to an important project and collaborate with a talented group of interns and engineers.
I also developed a newfound appreciation for often-overlooked aspects of engineering, such as quality control, which I now recognize as a critical step in product development. This lesson has left a lasting impression on me.
I hope to return and contribute further to the company's mission and be a part of more projects.
