Anyang, South Korea, April 14th, 2020 – Everything RF recently had a chance to interview RFHIC’s Co-Founder and current Chief Technical Officer (CTO), Samuel Cho. Based in South Korea, RFHIC is a leading developer of RF & Microwave components with a comprehensive product portfolio from discrete to integrated high power Sub-Systems, utilizing the most sophisticated technologies, including hybrid solutions of GaN and GaAs.

Mr. Samuel Cho has been involved in the development of RF and microwave components and systems for over 30 years. He holds a BE degree from Kwangwoon University, a ME degree from Yonsei University, and a Ph.D. degree in RF and Microwave Engineering. 

Q. Can you give us a brief history of RFHIC? When was the company founded, and what was the objective behind it?

Samuel Cho: RFHIC Corporation, which stands for Radio Frequency Hybrid Integrated Circuit, was founded in 1999. It started with an incurable need for cost-effective GaAs components for satellite applications within South Korea. In the beginning, RFHIC developed mainly using GaAs components but also saw the vast potentials of GaN technology, which led us to develop and provide GaN-on-SiC solutions commercially for telecommunications back in 2004.

After successfully commercializing GaN on SiC for telecommunications, we diversified our telecom customer profile and expanded into the defense sector. After multiple successful defense and commercial radar projects, we established name-value domestically and overseas with top global defense contractors. We recently entered the RF energy market targeting high power industrial, scientific, and medical applications. With the expansion of our product portfolio, we have become the world’s first and only GaN device to systems manufacturer.


RFHIC's one-stop-gan solution

Q. What products and solutions does RFHIC develop? How has your product portfolio evolved over time?

Samuel Cho: RFHIC is the first and only GaN device to systems solution provider in the world. Offering customers a “one-stop-solution for GaN SiC transistorsGaN SSPAs, and high power GaN solid-state sub-systems for telecommunications, radar, EW, and RF Energy applications. Our initial product portfolio consisted of mainly GaAs and GaN transistors and power amplifiers for telecommunications and defense. Still, over time as we expanded our focus segments, we also broadened further upstream by expanding our product portfolio to the sub-system level. By doing so, it provides our customers with turnkey manufacturing, streamlined communications, better product fit, and, most importantly, significant cost-savings.

Q. Are you a fabless company? Which Fabs do you work with?

Samuel Cho: Yes, we are a fabless company, and I think it is one of our key advantages for providing our customers with cost-effective, high quality, and fast products. Being a fabless company allows us to experiment and utilize different technologies and materials more suited for our customers. Also, by being fabless, it will enable us to allocate our financial resources more towards R&D and Sales allowing us to go broader and deeper in our core products. Wolfspeed is one of our several GaN wafer suppliers, along with others in multiple geographical locations for risk mitigation purposes and competitive supply chain strategies.

Q. What about GaN Technology made you decide to focus on this technology most?

Samuel Cho: As I mentioned earlier, RFHIC started developments with GaAs and LDMOS. Still, we foresaw the benefits of GaN technology, which led us to migrate towards GaN- specifically GaN on SiC technology. GaN is a wideband gap (WBG) semiconductor material that can sustain a high breakdown field and high saturation velocity than conventional semiconductors like silicon or GaAs. It also exhibits exceptional thermal characteristics by efficiently dissipating heat through high thermal conductivity SiC substrates.

But I do see GaN on SiC running into physical limitations within the next 3-4 years for higher power applications, which is why we have been developing GaN on Diamond, RFHIC’s next-generation semiconductor material. Diamond has five times the thermal conductivity of SiC, allowing GaN devices to operate much cooler significantly, enhancing reliability or drive it harder to produce two times more power from the same size device. This technology will allow devices to operate at much higher power levels and frequencies without hindering the form factor and enable future developments in the field of radar, Satcom, and various industrial applications.

Q. How has GaN technology evolved over time? What applications do you feel are best suited to this technology?

Samuel Cho: GaN technology was just a research topic at universities ten-twenty years ago. Over the last decade, it has significantly improved in performance, cost, and reliability due to mass adaptions in various applications, not just for LED. I believe GaN technology is best suited for all semiconductor applications from switches to even CPU. However, if I am specific to GaN on SiC technology, it is best suited for high-power RF & MW applications, especially for 5G, Radar, EW, and RF Energy.

Q. Do you also develop amplifiers based on LDMOS technology? What is your view on GaN vs. LDMOS technology for wireless infrastructure amplifiers?

Samuel Cho: We started with conventional semiconductors like GaAs and LDMOS, so we do have a lot of RF & MW expertise on both compounds. But we foresaw that there would be a massive shift in technology within the RF & MW industry, especially for high power products leading us to pursue the development of GaN SiC solutions. Currently, we solely develop GaN on SiC transistors and power amplifiers for wireless infrastructure applications. With the deployment of 5G, efficient high power systems with small form factors are critical. With GaN’s key performance features, I believe it will continue to replace conventional semiconductors like LDMOS and GaAs for various applications. As price comes down, we expect it to gain massive adoption from all industries.

Q. What differentiates RFHIC from other GaN amplifier manufacturers?

Samuel Cho: RFHIC has been within the RF & MW business for over 20 years now, giving us extensive product breadth, RF & MW expertise, and manufacturing know-how. Also, with our world-class GaN transistors and power amplifiers, we can go further upstream to the system level, allowing us to expand our RF & MW expertise and product portfolio. RFHIC’s one-stop GaN solution business model will enable customers to get their GaN solutions, whether COTS or customized all in one location, reducing overall capital expenses and significantly shortening project schedules to get to market faster.

Q. What market segments do you cater to? Which is the largest segment for you?

Samuel Cho: We cater to three key industries: Communication infrastructure components for telecommunications, power amplifiers, and high-power sub-systems for military/commercial radars and industrial, scientific, and medical (ISM) applications. Currently, our telecom business is the most substantial portion of our revenue, but we do foresee our defense and RF Energy business expanding significantly within the next couple of years.

Q. Who are your customers? Geographically, where are they located? What is the % break up by region?

Samuel Cho: Our customers for the telecom side of the business are Samsung, Huawei, Nokia, and Ericsson. For the defense front, we have top global defense and aerospace contractors such as Raytheon, Lockheed, L3Harris, Leonardo, Saab, Northrop Grumman, and much more. We have a very global and diverse customer portfolio within Europe, the US, China, and domestically. If I had to estimate, I would say that about 60% of our overall sales are overseas and 40% are domestic.

Q. RFHIC has an extensive catalog of standard products. Do you also develop custom products for customers? What percentage of your business is Custom vs.? Standard Products?

Samuel Cho: RFHIC offers a broad range of commercial off the shelf (COTS) products as well as customizable products for our customers. RFHIC offers custom design solutions at unbeatable speeds (2-4 weeks), shortening customer’s project schedules. Therefore, getting products to market faster. Most of our key suppliers are within a 40 min distance from our production facility, enabling faster development time and lower costs.

I would say 80% of our products are customized, and 20% is COTS. But with that said, I believe our broad COTS solutions are what make us more capable of offering customized solutions. It shows potential customers our extensive expertise and capability in RF & MW applications. Our vast COTS portfolio offers our engineers a foundation, so they aren’t starting from scratch, enabling our customers to get to market faster and to meet their budget goals.

Q. What is your vision for RFHIC for the next 5 – 10 years?

Samuel Cho: I see us in the next five years developing high power products with RFHIC’s GaN on Diamond technology. I foresee RFHIC’s Diamond technology to be heavily used for higher-power applications, especially within the defense side, and later towards the RF Energy market.

I also envision us in the later future researching and developing products with various semiconductor materials like GaN on GaN and even Diamond on Diamond. Lastly, I see RFHIC becoming the best GaN RF & Microwave device to sub-system manufacturer in the world.

I want people to remember RFHIC as the best one-stop GaN solution provider, anytime they have a high-power RF & MW need.