Oral-History:Henry Kressel

From ETHW

About Henry Kressel[edit | edit source]

Henry Kressel joined RCA Laboratories in 1959, where he became vice president of solid-state electronic research and development. At RCA, he worked on research developments in light sources, light detectors, and integrated circuits, practical laser diodes and an early epitaxial silicon solar cell.

Kressel is an IEEE Life Fellow and was the founding president of the IEEE Lasers and Electro-Optics Society. He was a recipient of the IEEE Centennial Medal, the 1985 IEEE David Sarnoff Award for "contributions to electronic devices". Kressel was elected to the National Academy of Engineering in 1980, is a Fellow of the American Physical Society, and was awarded an honorary doctorate from Yeshiva University.

About the Interview[edit | edit source]

HENRY KRESSEL: An Interview Conducted by Michael Geselowitz, IEEE History Center, 31 August 2012

Interview # 638 for the IEEE History Center, The Institute of Electrical and Electronics Engineers, Inc.

Copyright statement[edit | edit source]

This manuscript is being made available for research purposes only. All literary rights in the manuscript, including the right to publish, are reserved to the IEEE History Center. No part of the manuscript may be quoted for publication without the written permission of the Director of IEEE History Center.

Request for permission to quote for publication should be addressed to the IEEE History Center Oral History Program, IEEE History Center, 445 Hoes Lane, Piscataway, NJ 08854 USA or ieee-history@ieee.org. It should include identification of the specific passages to be quoted, anticipated use of the passages, and identification of the user.

It is recommended that this oral history be cited as follows:

Henry Kressel, an oral history conducted in 2012 by Michael Geselowitz, IEEE History Center, Piscataway, NJ, USA.

Interview[edit | edit source]

INTERVIEWEE: Henry Kressel

INTERVIEWER: Michael Geselowitz

DATE: August 31, 2012

PLACE: New York City, NY

Geselowitz:

This is Michael Geselowitz and I'm in New York at the office of Dr. Henry Kressel conducting an oral history on behalf of IEEE. Dr. Kressel, if you could start by telling about your early life and how you got into engineering.

Kressel:

Well I was always interested in science and machinery from my youngest age. And when I was about seven or eight, I became intrigued with steam engines. I used to watch the trains go by, so it's just that I couldn't really figure out how steam engines worked and somebody started explaining it to me and I decided to build my own.

Geselowitz:

And when was this about?

Kressel:

I was eight years old. I was in France. I actually started putting together all the pieces, including the piston and everything else; and the big problem I had was the reciprocating feature which is, of course, the basis of the Watt engine. It took me a while to get that one right. So I build a little prototype and it actually operated and it had all the pieces. I decided from the youngest age that I wanted to be a scientist, to be an engineer. I came to the United States in 1946 and enrolled in high school here. Then I graduated in 1951 and I went to Yeshiva College and majored in physics and math. The Math Department was pretty amazing at that time; Professor (Jekuthiel) Ginsburg who I believe had started Scripta Mathematica. He was Chairman of the Department and Professor Arnold Lowan was Chairman of the Department of Physics and he had had a spell at the Advanced Institute, Princeton when Einstein was there. Einstein had recommended him to the Chairman of the Board of Yeshiva University to join the faculty and he was really a great physics teacher. So between those two I just majored in math and physics, and then I went to Harvard on a fellowship. I was a Storer Fellow but after one year I just couldn't find anything I was really interested in doing and decided I just needed a little broader view of the world. Somebody said, well, why don't you go to Business School. I'd never taken a course in accounting; I had no clue as to what it was. But I applied to Harvard and Wharton and got accepted to both but decided to go to Wharton because it was closer to my family in New York. I majored in Industrial Management and Finance at Wharton. I did a stint in the Army for six months in between, graduated in 1959 and joined the Burroughs Corporation. Burroughs at that time had a facility in Paoli, Pennsylvania, right outside of Philadelphia. They were building a computer to manage the Atlas Missile System which was the first intercontinental missile system that the United States deployed. So I was part of the development team for the hardware. It consisted of germanium transistors strung together; this was before integrated circuits, 1957, '58.

One day I wandered into the library and picked up a textbook on solid-state physics and it had a big description of transistors. I thought that was more interesting than trying to build big computers so I looked around as to where I can get started in the transistor industry; this was 1959.

Geselowitz:

This is very early.

Kressel:

Oh, it was very early. Oh, sure, it was only germanium transistors at that time. So I answered an ad in—I think it was The New York Times—for junior engineers at the RCA Corporation. They had a newly formed solid-state division in Somerville, New Jersey. So I went down and applied and the guy who interviewed me was Dr. Adolph Blicher. He was a Polish scientist who had defected after the war, came to the United States. He gives me a piece of chalk and he goes to the board and says “explain to me how a transistor works.‘ It just happened that I had read the textbook so I just went and showed him a junction transistor and showed how it worked and how it amplified and switched and do all that good stuff. And he said okay you have a job.

Geselowitz:

[laughs]

Kressel:

So that I started at $6,700 a year as a junior engineer. Within two years I had developed the first production transistor, a silicon transistor that RCA built, which is the 2N2102 switching transistor which is still available today. I think it's manufactured by ST Microelectronics; you can go to Google and Google it.

Geselowitz:

They still make discreet transistors?

Kressel:

2N2102, yes, it's still available. I think they’re 5 bucks a piece. Anyway, what happened was that the Marketing Department called that the universal transistor because you could do almost anything with it you wanted; just a nice device. And so I set up the first factory to make that stuff, which was great experience. I mean, I was a very young person.

Geselowitz:

But you already happened to have a background industrial management as well as applied physics!

Kressel:

Yes, I already had a background in Industrial Management. This is really where my MBA really came in very handy.

Geselowitz:

And where did they put the manufacturing facility?

Kressel:

In the back of the building in Somerville. It was in the back of the lab where I developed it. I used to work two shifts, and I trained the operators. I did that for two years. And then—I don't know exactly how it happened—but there was another department that was being set up to work on microwave devices. So I decided to talk to the people putting that together. There was a requirement at that time for the space program to build a power source to replace vacuum power tubes. The basis of that is called the varactor, which is a variable capacitor—which is a PN junction specially constructed. I spoke to the guys who were building the radio systems about the power device in the radio that was used to communicate between the lunar module that was landed on the moon and the module that continued to orbit the moon.

Geselowitz:

Interesting.

Kressel:

It needed a very lightweight and extremely rugged device, so you can't use tubes; it'd have to be all solid-state. I came up with the varactor design which ended up being used. I had a chance to meet one of the astronauts that had used those radios and I told him I had helped put those radios in place. Oh, they worked like a charm, he said. It was not Armstrong. It was one of the other guys that was in the lunar landing program.

Geselowitz:

Was that a subcontract from Grumman to RCA?

Kressel:

Yes, probably. At the same time, Dr. Blicher remained my mentor. And he was a wonderful man. He had a PhD in Physics from Warsaw University. And he said,” you know you really should go back to school and get an advanced degree. A Master's is nice but I think you really owe it to yourself to spend time. “ So I applied for the RCA Sarnoff Fellowship. There were two people selected from the whole corporation every year to go all expenses paid to university to get a PhD. If you didn't have a Master's before you couldn't finish it, so you typically would just go right into the PhD program. I applied and I got one of those fellowships and went to University of Pennsylvania. I joined the Material Science Department. I didn't want to go into the Physics Department because I was more interested in the applied side. I was among the first students to go to the Laboratory for Research in the Structural Matter for which the U of P had gotten a grant from—I believe, it wasn't DARPA, it was before DARPA. No, on second thought I think DARPA was already there. They funded a number of universities to establish research centers for materials research. I decided to work on materials. I didn't know what kind of a thesis topic to pick, so Dr. Hofstadter, who had been at Bell Labs and who was the professor doing semiconductor research, was one of the people I spoke to. He said, “why don't you do a thesis in semiconductor materials? “ I said “well, yeah, okay, maybe I'll do that.‘

The following week there was a seminar by a scientist working for DuPont—DuPont Research Laboratories. And what he talked about was the impact of shockwaves, very high intensity mechanical pressure, going through materials, which has very interesting properties because you basically just destroy the lattice and put it together again, leaving defects behind. It was not really understood what the residual impact was on these materials. I went up to him afterwards and I said would you mind letting me use the facilities at DuPont to do some of this materials stuff. I'll do the analysis at Penn and, of course, credit DuPont for any of the research that I do. He said, absolutely, love to do it. So I studied the impact of shockwaves going through nickel and did the electron microscopy. I did the electronic materials studies. Actually, part of my thesis was to study the electronic impact of defects on connectivity so I did a lot of modeling. I finished my PhD and thesis in two years and I published five papers. This was a record at Penn.

Then I came back to RCA from Penn in 1965. And first I went to the Solid-State Division in Somerville but I just didn't particularly enjoy being there so I said I transferred to the RCA Laboratories in Princeton, now called the David Sarnoff Research Laboratories.

Geselowitz:

If I can interrupt for a moment—

Kressel:

Sure.

Geselowitz:

By this time had you become aware of IEEE?

Kressel:

No.

Geselowitz:

You were still not aware of IEEE?

Kressel:

Correct. I'll get to that in a moment.

Geselowitz:

Okay.

Kressel:

And so I transferred there in 1966, At that time it was a very open environment. People could choose their own projects from among the things that were going on. And people had their own laboratories. It was not that easy to get your own laboratory, but if you had a project that was funded, you could team up with others and have an opportunity to do interesting things. I started to look for an exciting project. So I was wandering around talking to people and one of the guys I talked to was a Greek scientist named George Dousmanis. I'll never forget his name. He showed me how he was working on semiconductor lasers under a contract from the Signal Corps. Now why was the Signal Corps interested in that? Because they were interested in building a solid-state infrared light source to guide missiles. It was actually at 9,000 angstroms, which is in the near infrared. The idea would be that you would be illuminating a battlefield target with these laser sources. And it was better than using a klystron or whatever other light source you would have at that time.

Geselowitz:

Other ways of generating infrared?

Kressel:

Yes, like the way it was done in World War II. He showed me this laser and when you turned it on, it would just fail in minutes. I said,” well, it just doesn't look too practical—it fails.” “Well, “he said,” you know something, it is really good physics and it really doesn't make very much difference because if we make enough of them, the experiments will be okay.” George Dousmanis shortly thereafter dropped dead of a heart attack—and he was a young guy. Anyway, I went to his supervisor, Dr. Henry Sommers, and I said I'll take over the contracts. So he asked, why do you have to work on this, when nobody was really interested in the subject. I told him that I just really had to understand why the threshold current density was so high and the causes of failure One of the reasons these devices burnt out was because the threshold current density was, like, 100,000 amps per square centimeter, so you can only pulse them, And worse than that, they were very erratic. So because of the work I'd done for my PhD thesis was on defects, dislocations and point defects, I figured this had to be related, nothing that random and unpredictable could be just natural. So I started to study the cause of reliability degradation, which I discovered was due to crystal defects. The idea was then to reduce the threshold current density, and, working with Herb Nelson, I came up with the heterojunction laser, which is today the basis of all the lasers in the world this work was independent of the work that was going on at that time in the Soviet Union by Alferov. Nelson and I published our work. We obviously did not know any other work going on at that time and, when I met Dr. Alferov later on we compared views. So we came up with heterojunction laser independently of any other work. There was also work done at Bell Labs, but I won't go into the issue of precedents. We at RCA came out with the first commercial laser in 1969. We made these heterojunction lasers available for general use. One of those applications was a very important one, which was in air to air missiles. Air-to-air missiles had a problem because the fusing system was heat-seeking. In other words, you would have a heat-seeking fuzing guide at the head of the missile and it would go where the engine of the target was and when it got close enough it would blow up. The trouble was that a plane would do evasive motion and the missile would not be able to keep up—in other words, if it lost sight of the engine it would just go right past. So the idea was, and this idea actually came from the guys who manufactured the missiles on the West Coast, to put a laser diode at each corner on the belly of the missile. The laser would light pulse and if it would hit metal and reflect back it would blow up. So it was a proximity fuse in effect, but based on lasers. That was really the first application of semiconductor lasers—pulsed high-power semiconductor lasers which I developed. The other early application was in simulated warfare. It now part of toys, I guess. You put a laser into a rifle and you put a detector on people training -- if the laser light hits the detector, it's a hit. So the U.S. government sponsored a company—I think it was Xerox, to actually develop these warfare systems for training, and I believe they're still used today. So we provided the lasers that were used for that. The communications applications really came later just because you needed a continuous wave operation, you needed high reliability and you needed fibers, and all those didn't really come together until the early 70's. In fact, I traded lasers with the Corning labs for fiber optic cables before they became commercial in the early ‘70s. So the work that we did on the lasers that we made commercially available actually found a very practical applications. These applications are here to this day and semiconductor lasers enable the world’s data and voice communications. I am very proud of my contributions to enable that.

So on the IEEE: I became interested in the IEEE in the early 70's. I actually joined one of the technical societies—I believe it was the Microwave Theory and Techniques Society because there was no specific group at that time focused on what we now call photonics. And there was no publication for it. So what I thought would be needed is a spinout which would be an IEEE Council, first, publishing a journal of quantum electronics. And so we first had a Council of Quantum Electronics and then became a Society. It became the Photonics Society.

Geselowitz:

Now a Council in the IEE parlance means that two or more societies—I think they were still called Groups at that time—get together to work in a new area together.

Kressel:

Right.

Geselowitz:

And these groups or societies get together to publish a journal. So, who partnered with the Microwave Society?

Kressel:

It was Electron Devices,

Geselowitz:

The Electron Devices Society, okay. So you got together and you had a Council and you started a journal?

Kressel:

Yes, we were still a Council and then the idea was to have a more focused journal which became the Journal of Light Wave Technology because the feeling was that the Journal of Quantum Mechanics was not engineering-focused. The Journal of Light Wave Technology is engineering focused. That's how from being the chairman of the Council, I became the first President of the IEEE Quantum Electronics and Applications Society (QEAS). And the one thing I thought was important—because I noticed that some of these IEEE societies had membership leadership that never changed—was that the term of office should be very short. So I made sure that I obsoleted myself. I think at that point we had a term of office of only one year or maybe two years. I just made sure we had a succession set up. That was really how I got involved in the IEEE.

Geselowitz:

How long did you stay on board after you were President?

Kressel:

I don't remember. Not very long. I really feel it's important in societies that you have fresh membership leadership. A) you've got fresh ideas and, B) it's one way to maintain the interest of young people—getting distinction and the opportunity to become an IEEE Fellow and things of this nature.

Geselowitz:

Did RCA encourage you to get involved in IEEE? This must have taken some of your time.

Kressel:

Well the funny thing about RCA, it was an amazing company. An amazing, absolutely astounding place in that nobody, ever, said anything at all about the time I spent on the IEEE activities. I think they felt it was important to do so. Part of the professional responsibilities was to publish and to participate in IEEE activities. So no one ever said a word. I got all the support I ever needed. I used to have all the meetings at Princeton and I did quite a bit of travel to meetings in Washington. The important thing was to get the funding right because these journals obviously don't make money so you had to make sure that the council and that the Journal of Light Wave Technology had the right sponsorship. It was not just what LEOS [Laser and Electro-Optics Society, a later name of QEAS] was then; it was still cosponsored by the Microwave guys. In fact, I think we had three societies, but I don't remember exactly. You could look it up. In any case, it was a collaborative effort

Geselowitz:

Did you also, besides, the journal side, also often emphasize conferences? Was there a main conference?

Geselowitz:

Yes, that's the other thing, of course, the conferences. We set up a specialty LED conference when light-emitting diodes were still relatively new. And then we had CLEO [Conference on Electro-Optics then we also had a conference on fiber optic communications. Yes, I was very active in conferences. We had the first of the fiber optic conferences in Williamsburg, Virginia. The big issues at that time involved fiber optic connectors and device the reliability. Making a laser for fiber optic communications required a mean time to failure of 100,000 hours. And certainly you had to think of undersea cables, because to get lasers with that kind of predictive lifetime was hugely difficult. So we spent a huge amount of work at RCA developing lasers for those applications. And, yes, I can honestly say if I had not done my PhD thesis on the impact of defects on materials, I would never have focused as I did on solving that problem. It is well understood today that crystalline defects have a major impact on limiting the life of lasers so you have to be able to screen for them, and you have to have manufacturing techniques that ensure that you don't introduce defects. I mean, there's a whole science. It's not taken for granted. People forget the humble beginnings of that. In fact, we published a paper in 1968 that showed a direct correlation between defects and reliability. You can actually watch the laser defects move. You can watch the laser light where the defects are, it's dark. It became dark because of the defects. But all that progress I really credit to an outgrowth of having focused on defects in metals and applying what I'd learned.

Geselowitz:

And what were the main tools for analyzing materials? The same ones you used in grad school, such as crystallography.

Kressel:

It was a lot of crystallography. Actually those defects, on the optical microscope you can see them. And then we introduced scanning techniques with electron beams and you could actually light up the sample. You light up the diode, for instance—or whatever it is—and it's very bright where there are no defects. When the defects are there, it's dark. And you can just image it. I have that stuff in my book; I have images of that. My textbook. In 1976 I started to write a textbook on heterojunction lasers and LEDS with Jerome Butler. The issue that we really were focused on at that time—this was the 70's—was to understand not only the electronic properties but the optical properties of structures. How do you manage the control of light, light paths, the optical and mode guiding, the mode properties? Because you really wanted a single mode laser in order to allow optimum coupling into fibers. The fiber core was like 5 microns in diameter. So if you had a small laser, you wanted a single beam going in and it had to be a single mode. So we did a lot of work on analyzing that.

Geselowitz:

And did RCA also encourage you in writing a textbook? Because that seems like more something an academic would do.

Kressel:

Oh, well nobody encouraged anything. The funny thing about RCA at that time which is really unique is that people were interested in doing things in multiple dimensions. Because all this was happening, I kept getting promoted and I became a group head, a laboratory director and then vice president. I always maintained an interesting strategy for that, because I always loved doing science. So I maintained two facilities. I always had a laboratory and my own technician doing my own work, and I continued to publish my research. And at the same time I had an office. And the office got bigger as I got promoted; as a vice president I had a really big office and big secretary office, but I used to spend maybe, I don't know, less than half my time there ,so people could always find me in my lab actually doing things. But I did none of my writing during the day. I published over 120 papers and so forth, but I always did this at night. But at the same time I think I had, like, 31 patents in a matter of 10 years. So it was about 3 patents a year, which covered some fairly basic things in a lot of areas. As my responsibility changed, I did research on solar cells. In fact we got the first grant from NASA for a low cost, high volume solar cell which was non-crystalline. The big industry today is non-crystalline solar cells, that is, silicates. One of my forecasts when I got this contract was we're going to make solar cells producing electricity at half a dollar a megawatt, which if you convert that in terms of dollars at this point, it's about $1 in today's dollar. And today it's moving toward $.50 in current dollars. This was in the '70s. I guess this is just a little prophecy that came true. The idea was that you did not need perfect silicon to make highly efficient solar cells. We really studied the interaction between the properties of the silicon and the efficiency of the cell.

Geselowitz:

Now how local was photonics research at that time? You mentioned the Soviets working on it.

Kressel:

Yes.

Geselowitz:

Because, in the 1980's, IEEE had a big issue of wanting to be more global and less U.S.-centric. At the same time for some societies, the nature of their research was very much focused on military application and getting funding from NASA, from DARPA, and from the rest of the Department of Defense. And that made it more difficult to get conferences, for example, to present classified material.

Kressel:

Well it's a good point. It really turns out that the potential of semiconductor lasers and LEDs caught on fairly quickly because it was pretty obvious that if you can replace a light bulb with a solid state emitter, it's a good idea. There are many people who really thought, even certainly in the 70's, that semiconductor lasers were just never going to be either low enough cost or reliable enough for anything but military applications. And one of the things we did in the mid-70's, in my group at RCA, is we took a contract from the Navy to build a prototype for a fiber optic system using single mode lasers. This was way before any kind of commercial ideas. We actually did prototypes in the lab. We had demos that actually showed communication systems going. We got some of those because I went to Corning and swapped some of my lasers for a few kilometers of their fiber, even though those are multi-mode at that time. We built a demo and the level of interest was amazingly low. People just couldn't visualize that you could put glass fibers out there, put the kind of reliability into it, couple these teeny little lasers that seemed to die by almost blowing on them, and just imaging putting this out in the field, putting them onto towers.

Geselowitz:

Or under water?

Kressel:

Or putting them under water, or into a sewer hole. When you went to those conferences, all you heard were people complaining that this was missing. The only ones who believed in it were the guys in the government. The Naval Research Laboratory believed in it. Tom DiLorenzo provided some of the funding—he should get huge credit for that. DARPA also believed in it. But the commercial interest was very low; I never really got much encouragement from the commercial guys. The communication people at RCA pooh-poohed fiber optics. I remember having internal meetings and they said, no way. That it's not interesting. You've got to use coaxial cables and then there's going to be satellite communication—and who's going to put out these fibers anyway? But we persevered and we got a lot of grants from the government in order to make that go. So having conferences where the Soviets would be invited, to your point, was not something that was easy. And the Russian work was really hidden from us; we learned nothing from what they published.

Geselowitz:

They did not publish in your IEEE journal?

Kressel:

They published usually in the Soviet Physics journals, but we learned practically nothing from them. In fact the big debates as to whether it was electronic confinement or optical confinement, the real advances, were really done in the U.S. And we were definitely in the forefront of that. Now Bell Labs and Western Electric were late to the party. Corning was really the first as far as I'm concerned in understanding the implications of mass production of fiber optics. And so of course the guys at Bell were working on lasers and all that, but they really never solved the practical problems.

Geselowitz:

Hm-mmm.

Kressel:

At least to my understanding. The guys at Western Electric that had the systems work to do ended up buying commercial lasers. I don't believe they used internally developed components until much later. The Japanese were very active. I must say of the work that was done on lasers and especially single- mode lasers, the Japanese work was outstanding. If I look at the international scene, STL in England was important, because one of the structures that we had come up with was the multi-heterojunction laser. We called it a large optical cavity, which actually today is what you use to control the modes. And STL did some excellent work on that.

Geselowitz:

That's where Kao did the initial theoretical work, right?

Kressel:

Yes

Geselowitz:

At STL.

Kressel:

The single mode laser work was done; it was the single mode fibers. So it was an international effort, but to go from a laboratory to a commercial product is a huge task. I always viewed my job at RCA to advance the commercial markets either through sales to the government or through commercial sales. So we set up a commercial laser business in the Lancaster division. They're the ones who produced the commercial lasers. In fact, later, come to my office, and I'll show you an ad that we ran. I'll show you on the way out after the interview. So my involvement with the IEEE was really during the formation of LEOS and on the journal. And in 1983 I decided to leave RCA and join Warburg Pincus which at that time was one of the earliest of the venture capital firms. I joined to start the technology practice. Lionel Pincus who was the founder of the firm was looking for someone to start technology investing. I had never met a venture capitalist in my life; didn't know anything about it. I literally knew nothing about this industry. But he said why don't you come and try it and if you like it and if we like you….

Geselowitz:

How'd you get together, how'd you meet him?

Kressel:

By accident. I wanted to work in a lab to develop LEDs which RCA decided not to mass produce. One of them was a green LED which was very efficient at the time. Somebody in the marketing department of RCA worked with me on the project and thought that we should go into commercial production with this. We decided that unless you really made a commitment to a big family of display products—if it was a one-off—then it didn't make any sense. Well, he left and joined Warburg Pincus. I happened to meet him quite by accident on the street in riding to lunch. He brought me here and I met Lionel Pincus and I met John Vogelstein—those are the two who at that time were head of investing. And that's how I came here.

Geselowitz:

You did actually have the Wharton background.

Kressel:

Oh, of course. People always ask me the value of a business education. I think it's extremely valuable, but not if that's all you do—then you don’t know anything. I think if you combine that with industry expertise, it's a valuable toolset. I assume this: for some of the things that we covered, I had first-class teachers in economics. This was University of Pennsylvania, and Wharton's a top school for corporate finance accounting, for industrial management. And learning all those things and spending two years and just having some terrific classmates really opens you up to really understanding issues and increases you awareness. But I always insisted on coming back and going on the technical path. I did not want to go into the business side of RCA. In fact I kept turning down offers to be promoted. I didn't think I would like it until such a time as I felt ready to try the other side.

Geselowitz:

Okay. To wrap up, actually I just need to ask you when you switched to research and engineering into venture capital and you came here in order for Warburg Pincus to start up the technology side, what was the connection? What technologies did you focus on early on in your investing career?

Kressel:

Well I actually made up a list of about five or six areas that I thought—this was 1983, right—would show above average growth. Growth through technology innovation, and obviously it included semiconductor devices, especially integrated circuits, and optical communications. Another area that I was interested in was software for industrial management and industrial process management. And still another one was materials. I ended up just looking at those four, and I actually made investments in all of them. So let's just take them in order. Actually, the first investment I made was in a company called EPITAXX, which took over some work which we had done at the RCA Laboratories such as avalanche detector devices. Greg Olsen and Vladimir Ban and most of those guys that worked in my group at one time, worked in that laboratory. And we commercialized it. I think it was the first independent company selling detectors for fiber optic communications. The company was eventually sold to Nippon Sheet Glass. And it was a profitable investment for us. We did Covad Communications, one the first of the DSL providers for homes and businesses. This was in the 90's. Level One Communications which became a leader in Ethernet connectivity chips. It was eventually acquired by Intel. In the semiconductor field, we are also investing in a successful new company in China called RDA Microelectronics, which makes components for handsets. And to kind of top off my investments, we funded part of the buyout of Avaya from the old AT&T.

Geselowitz:

Hm-mmm.

Kressel:

The telephony side of AT&T. First it became part of Lucent, and then we financed the purchase of the company. In the United States there was a department of AT&T called Bellcore—the name was changed later. Anyway, Bellcore became an independent company and it was in 2005 when Warburg Pincus ended up owning 50% of it. It was later sold to Alcatel. I am happy to areas that I thought we would be investing in and were have actually successful.

Geselowitz:

That's great. And so it all came together.

Kressel:

It all came together.

Geselowitz:

Okay. Is there anything else you'd like to add today?

Kressel:

No, just that education is never wasted.

Geselowitz:

Great. Well that I can see that in your case, so thank you very much. I really appreciate your valuable time.

Kressel:

My pleasure. Thank you.