Oral History Interview with Dale Morton
Conducted by Frank T. Zimone (FZ) on April 26, 2005
FZ: We are at the 48th SVC TechCon in Denver, CO, and today is April 26, 2005. It is my distinct pleasure to conduct this interview with Dale Morton.
I’ve had the pleasure of working with Dale since 1996. I think I know just a little bit about him. I think you’ll find that there is much more to this man than meets the eye. I’d like to start of by asking you, Dale, if you can describe to everyone your background and education and how that transpired to get you into thin film coating.
DM: Well I went to high school in Ohio. Went to Ohio State 1955 to 1959. Graduated from Ohio State and taught for 8 years, 2 years in the Bryan, OH, city school system, and 6 years at the Webb School in CA.
While teaching, summers we were sort of off, so I ended up getting my MS degree in 1962 in Education, with physics, chemistry, mathematics the other majors. One summer while working at General Dynamics in Pomona, CA, they asked me to come on fulltime. I couldn’t at the time because I had accepted a job teaching the following year. But during the following year I worked for them part-time with the school’s permission. They asked me to join on again at the end of the school year. I decided it would be interesting to try it.
The work there was relatively interesting. I was mainly doing electron microscopy in a Hitachi HS 6-inch electron microscope. I did similar wavelength interferometry for thickness measurements, working on a program for characterizing the initial nucleation, deposition and growth of films.
FZ: So that was your first exposure to thin films?
DM: That was my first exposure to vacuums and thin films, other than the traditional soap film in physics classes. We were interested in the growth rate of the films. Back in those days, someone had come out with a quartz crystal monitor. The old analog thing would wail away when you deposited. It turned out that there were deposition rates that were detectable well above those at which we wanted to deposit. So took the quartz crystal and hooked it up to a Hewlett Packard counter and extracted the last two digits on the signal. So we had 100 Hz on the tail end of the digital signal. We could then draw on a strip chart the rates at which we wanted to deposit, and we would manually control the deposition so that it would follow the lines on the strip chart recorder. That’s the way we did initial depositions.
The next study probably went on for 2 or 3 years. The contracts sort of dried up. So we had to do some practical things. General Dynamics was making the sidewinder missile (I think). So we got involved in doing some optical coatings for a development program on the optical guidance system.
FZ: What was your role at that time? Were you an engineer?
DM: My role at that time was as Senior Physicist on the project. I was basically doing vacuum depositions there. When we deposited the coatings, we characterized them spectrally. That work didn’t require an electron microscope of course.
FZ: Did you learn your techniques on the job? Were you mentored by someone?
DM: I had all on-the-job training. I had no vacuum experience in college.
FZ: No thin film experience at all?
DM: Angus McLeod had written his first edition of his book, which had just come out at about that time. I learned optical coating design actually by reading that book.
FZ: So you learned there?
DM:I didn’t get out of tutoring, especially initially. I left General Dynamics. I had started there in 1967, and I left in 1972 and went to Texas Instruments (TI). Frank Sulzbach hired me at the time to finish up a nonmelt project. Coating work at General Dynamics had involved sputtering and evaporation. I had sputtering experience. The nonmelt contract called for nonmelt techniques for depositing coatings. This involved sputtering and reactive plasma deposition. So either I talked a good story or he was desperate or something, but I got the job and moved to Dallas in late 1972.
FZ: How big a group was at TI when you joined them?
DM: The thin film design people was a group of four or five and the optics designers, which were in another building, was a group of 10 or 12 people, and they all worked for Bob Crossland who headed up the optical design group. Our design engineers were all down at the Lemmon Avenue plant because it also had the optical coating deposition facility. The optical coating deposition facility was from the IM Mann Company, which TI had bought out in California and had moved to Texas. They had since upgraded the equipment. They had two 750 Balzers machines, two 1050 machines, and were adding a third 1050 machine in addition to all of the older manual machines from the IM Mann company at the time I was hired in.
The nonmelt contract didn’t involve any of the regular PVD deposition equipment, but it was finished up in about a year. The contract was not renewed for the final year of the program. They never told me, but they gave me a job. One was to replace thorium fluoride, so I spent about 6 months studying mixtures and a variety of fluorides and chlorides and deposited the thin films and characterized them. I came up a couple of solutions.
FZ: These were all electron beam?
DM: Well these were mostly electron beam evaporated. Some of those materials could have been evaporated by boat, but we did them by electron gun. We actually had a pretty good solution to replacing thorium fluoride but the government didn’t require it. No one paid us for the work, so we didn’t implement them at the time.
I would say that around 1976, I was asked to take on the automation of the equipment at TI. My boss, Frank Salzbach, decided that if we could automate the equipment that we would all be able to run the equipment as well as our best technician, whoever that might have been. So actually it was close to a year before we finally got approval for the capital program to do a prototype machine. We got a $500,000 contract and went at it. Ten months later, we turned out an automated optical monitor vapor deposition machine. We didn’t have quartz crystals, so we had to the rate with the optical monitor signal also.
FZ: What did you do during that project?
DM: I was responsible for interfacing with the actual people who implemented the automation effort.
FZ: So you defined the requirements?
DM: Yes. So the requirements were that the computer should do everything that a technician does, as far as possible, up to but not including loading and unloading parts. But once you close the door, it should run itself from start to finish automatically and with an optical monitor signal. In 10 months we made a single-layer coating. After an additional month we made a multilayer AR coating, and it just snowballed after that. The intent was to do all the coatings that were done at TI at the time, about 30, and we were able to do that essentially. Of course the prototype machine didn’t do all of that, but once we had the multilayer AR coating, we also did a Narrow Band Filter for a guidance system.
FZ: That was almost 30 years ago, but it works only a little bit differently than it does now. Were there particular challenges?
DM: We had to use the TI computer (a TI 960B). TI made test equipment for the Army. Basically, we used the same equipment to run the machine. The computers were just bigger then. We had not only a machine coater but also a machine coating engineer who did all the machine coating. Actually, what he did was write the program language, which was Atlas (which was essentially speaking in an English sentence). You would have to use the specific syntax or form that was required. So “turn optical monitor lamp on,” would be a correct statement, or “turn optical monitor lamp off,” “turn electron guns on,” “turn electron guns off,” “apply 20% power to gun 1,” and so forth.
FZ: Did you have all the interfaces that were required? Did you have to invent something?
DM: They were mostly interfaces we sort of had to invent. Between the computer and the chamber was an interface bucket. The interface bucket of course had a motherboard, and you would put all the other boards (digital audio boards and analog audio boards) in to be used to run the circuitry. Then the machine language programmer also had to plate coat. We would test it out and do setup work, for example, the reflectance signal always had to be set up to some starting value. So “set reflectance value to 90%” would be the command. It would drive the gain to the optical monitor controller. A signal which we had to introduce into the system to give us the gain to the unit. I don’t think they drove the actual power **** on the optical monitor lamp, although we did have digital turners that turned the large tracks on the resistance sources, which back then these were these heavy bolts you pulled out, rotate over, and push back in. So instead of that we had these **** turners on the pump that we had to call them “digital actuators” or something like that because the VP who had to approve the program didn’t like the term “**** turner.”
FZ: So the first prototype that was built was considered a success?
DM: It was a success. It worked quite well. We went in for the money for automating five more machines. That was approved on the first or second go-around, but within 2 or 3 months. Over a 3-year period, we upgraded the automation. We got rid of the **** turners. The electrical engineers took the time to translate the hardware documents we had and were able to duplicate the circuitry inside the vacuum pump controls.
We also improved. We actually had zero level balancing on the optical monitor, which were able to do although we never had to use it. After 3 years, we had 85% of it automated. The first chamber was then upgraded to the same level as the other five. That completed the automation effort.
During the course of that, I was made manager of two groups. One group was the automation group and the group responsible for buying equipment, and the second group was the process engineers that sustained ongoing processes. Then we went into a mode of buying equipment that was automated on the outside and that matched and met the contract on the first machine that we bought. We bought two more from Denton, and then following that we also bought three machines from Televac that were automated. Soon after that I left TI.
FZ: At this time were you at all active or participating in the SVC?
DM: Yes. It was actually due to the automation that I became acquainted with the SVC, well I guess Peter Denton introduced me to the SVC. I think Peter Denton referred me to a GE person who subsequently called up and by asking so many questions, they conned me into doing my paper on the automation.
FZ: Was that the first paper you had given at the SVC?
DM: No that was actually at the New Jersey Vacuum Society meeting. Soon after that I got involved with the SVC and have been active in it ever since then.
FZ: That much we know! From TI where did you go?
DM: After TI, I joined a company that was called Optical Product Corp in Dallas. They were in the mode of going into production on some very state-of-the art filters that were being built at the time.
FZ: What were some of those?
DM: There was the M22 binocular filter, which was a high-density optical filter for which the requirements were classified. It blocked out essentially five different laser wavelengths in the visible and near infrared and required a not exactly high photoptic, about 35% at the time, but the person using the binocular would be protected from all the laser bands that were considered as a threat at that time. And they also had other laser protection filters that blocked similar wavelengths, but in different combinations.
When I joined them, I didn’t know what I was going to do. I didn’t really know that much about what they did. Essentially, I designed all the coatings that were designed after the time I joined the company and I developed production processes for them.
FZ: Can you tell a bit about what you designed and what other the techniques were available to them?
DM: Basically, they are blocking filters. But, they have to transmit in the visible. So essentially they were short-wave passthrough filters, except the ones that were blocking in the visible. For the ones that were blocking the visible, you would narrow the rejection band down to the point that it was only wide enough to accommodate the angle of incidence requirement for the filter, which had very high OD blocking. So you would have maybe 200 layers in the filter that would block visible and transient visible. A good example of that is the COC, which was the most stringent. It was same as the M22, but with optical photopic of 60, so we had to have 25% higher photo-optic level for that filter. Then for the blocking was basically just nearly enough to block out the visible part that was needed. In order to narrow the band down we had to use unbalance reflector stacks. Then because of the unbalance you would have to get the blocking requirement back up to that was needed. There were essentially about 300 layers in those optical filters.
FZ: Did you use any computers to support the design?
DM: Yes, we used Phillips at the time. The design of the filter was the easy part. The hard part is in the making of it. These filters were all optically monitored on wavelengths and directly on the part. We did not necessarily use the wavelengths that we were blocking, in fact that was the one innovation I supplied to the process for making the filters was to go a shorter wavelength in order to level monitor rather than turning point monitor. That increased the accuracy of depositing the layers and gave us higher yields. Eventually, the M22 yields probably got up into the range of 90%.
Also at that time I did the vision block process for military tanks, which was essentially a filter that blocked out the ruby light. It was 0 to 80° with a high transmission in the visible range. They did use a colored glass, an infrared filter glass, which cut out the longer wavelengths. That design was a fairly simple design, and although the initial design was supplied to DECASS using titanium dioxide and silicon dioxide, when we got the contract, my boss didn’t trust titanium dioxide and silicon dioxide filters that thick. And so we switched the titanium dioxide over to niobium peroxide. Then we increased the thickness to 86 layers. As far as I know that was the first that niobium peroxide had been used for that type of filter. Since then, I think other people have gone to using niobium peroxide.
FZ: How did you come up with using that material? Was it from textbooks or some other use in the industry?
DM: Well the other material that would have been used was tantalum pentoxide. Its refractive index is about 2.05 to 2.1. But we didn’t have ion guns at the time that would put out consistent layers. So we would use tantalum pentoxide and then silicon dioxide, but at the rate that they were doing it the tantalum pentoxide was absorbing. So after they had deposited four to six layers, they would stop the deposition and backfill oxygen to modify the atmosphere and bake them for around 10 to 20 minutes. Then they would take them back out again to deposit four to six more layers, so those filters took a tremendous length of time to deposit.
The niobium peroxide basically didn’t have any absorption, the refractive index was higher, so it took fewer layers.
FZ: How was that?
DM: It was a shoe-in; I knew it was there. If you look at a periodic chart, you’ll see titanium; you’ll see niobium; you’ll see tantalum. Niobium is in between, so it had to be a higher index than tantalum and it had to be potentially available material. As it turned out it was.
FZ: How long did you stay at this particular organization? And why did you leave?
DM: Well I stayed there about 7 years. We were bought out by IMO and merged with Vero. The Vero name was used because Imo bought Vero the year before. So they had all the people who worked for Vero there already. So we had to change our name, but that didn’t matter. Then they reorganized our group and eventually they brought in the group that was writing regular coding for Optical Mechanic Corp to sort of run us at the supervisory level. I really didn’t care much for that, so I was looking for another job. Strangely enough I got an offer from Optomechanics in FL, and a good pay increase and a 5-year contract. It all added up to a good deal, so I went for it.
I went there in 1994. That’s why I moved to FL. However, in less than a year, they went bankrupt. All labor contracts were null and voided by bankruptcy court. But it didn’t really matter because they were bought out by DRS. I stayed on for about a year. Then I was one of the last people that DRS laid off as the new people took over the country. I since found out that about a year later they laid off all the people who were involved in the buyout, and hired one of the original engineers back in the optics manufacturing shop. It was the guy who had headed it. They hired him to come back and get the shop back into shape.
I decided it was a little bit too early to retire, so I looked around. There was Denton Vacuum. Actually, I called them about 5 minutes after I found out I was laid off!
FZ: I can remember the first time I ever met you. It was by telephone. It was a Friday, and I was working and one of the few people in the plant when the phone rang. I decided to pick it up, thinking it might be for me. It wasn’t, but it was this incredibly polite and nice individual who was having a problem on a piece of equipment that we had supplied to Optomechanics. And this terribly polite and knowledgeable person was you. I can still remember hanging the phone up saying, “Boy, wouldn’t it be nice if he would come to work for us?” And just a few years later …
DM: It was probably about a year and a half later …
FZ: You got off the plane and came on up. From my perspective, you mentored and taught to our whole organization technologies and approaches that quite honestly we didn’t know were out there!
Can you take a bit of time and describe your technical accomplishments in the latest large block of time in your professional career?
DM: I think probably the most important of my Denton Vacuum experience beyond just the process know-how was the fact that we finally got an optical monitor working on the system that we could sell to customers. All I did was to keep badgering to achieve certain features and so forth until we finally did it.
FZ: I still have the memo that you wrote on what we should do in our vacuum systems. It’s taped to the wall behind my desk. It was quite germane what you wrote to address some issues that we really needed to address.
DM: Our optical monitor is pretty good now. We had the advantage that we didn’t have to incorporate rate into the control. So, the controls became significantly simpler. All we had to do was look for peaks and record them correctly.
FZ: What do you think was the most difficult project you had in your time spent at Denton? Was there one that kept you awake at nights for a little while? You always impressed me in that you looked as if you were very calm and very cool and just always took a very methodical and measured approach.
DM: I don’t think I had that many process challenges at that time. I mean we were supposed to supply processes for customers’ needs. On most of the jobs that we ended up taking, if there was a real process requirement, the customer was going to supply it, not us. And so we merely had to build the equipment to do what the customer wanted. We were very careful. But at least in machines going to China, our customer requirement was not very stringent. Even then, we would still have a few problems. But it was merely a matter of working at it until we got the problem ironed out.
FZ: Could you talk a bit about your work with ion sources because you have published quite extensively.
DM: Actually, I’m glad you brought that up because that probably was my major contribution at the company. When at Denton we had the CC104, and it was being studied Rob Danielson in the Machine and Coating Department. It didn’t run too well but it at least a vacuum where we could deposit films. He had done some depositions that would lead up to a vapor. I took the work that he had done and expanded on it. I actually found out how the ion gun ran. It didn’t make the best coatings in the world, but it made control index coatings.
We found out how you could increase the current and get a higher density to the film. I deposited films without ion assist in order to see what effects those films had. We did them in various textures and so forth. It was definitely a learning experience on the ion gun. The Application Lab machine at the time was the old 29 and it had a CC103 unit. I also found out we had a CC105, but there was something wrong with the cathode plate.
FZ: Is that when you introduced the Hastalloy bottom plates?
DM: Well when we ran the CC105 and the Integrity 29, I soon found that I could make much more stable films with it—first mainly doing titanium, niobium, tantalum dioxide, and silicon dioxide. We actually made a series of stacks. The 105 actually ran quite smoothly and nicely. And then they put the 104 in the Integrity 29 and much more stable films with that. Then they put the 103 back in the chamber and even more stable films with it, but the 103 was already passé. We didn’t build them anymore. In fact, I think we built two production lots of the 104s and then went to the 105s.
FZ: So if you look back on a technical career that started at General Dynamics, moved to Texas Instruments, went to what was ultimately Varo-Optomechanics, and then Denton Vacuum, what would you say was the most important thing you think you did, what would it be?
DM: I think it was the optical monitoring and TI because it was the hardest program. It hadn’t been run before. There was no one who had a machine that did optical monitoring. Ours, as far as I can tell, was the first machine that the optical monitor (only) did a complete, from end to end, monitoring in turning out an in-specification part. I mean that when we got all the machines running, they automatically just ran. They were never run manually after that. Until, I understand, the Maintenance Department said they couldn’t support the computers anymore. Then they tore them out! But they could still go back to manual because one of the requirements of our design was that everything could go back to manual if they needed to. In fact, they were designed in such a way that any component could go back to being run manually if desired.
FZ: What about some of the people with whom you worked?
DM: I think the “two Franks” are the people who had the most influence on me. Frank Sulzbach of course mentored and guided me. Then Frank Zimone at Denton Vacuum.
FZ: What did I do?
DM: Well you gave me the opportunity to do some very good work.
FZ: I think that you may have forgotten another important person your life who probably had a big influence on things. Can you tell me a little bit about Linda?
DM: Well, she let me do whatever I wanted to at work! Linda has always been a big support to me. She’s a very nice person. Actually, at General Dynamics in Pomona, I worked for Esther Krikorian who was a very smart person who had some very entertaining personal characteristics. But I learned a lot from her too!
FZ: Any regrets? Are there maybe things you wanted to accomplish?
DM: I hope to keep on working for a while. I’m always itching to get into some major projects, but I don’t see myself doing that any more. But if there were a project or two to offer themselves, I certainly wouldn’t turn them down!
FZ: Well, I see that as a personal challenge to keep you busy! Can you share with everyone here your experiences with the SVC?
DM: When I started out in the SVC, Peter Denton was actually the person who got me started in the SVC. After I gave a paper here for the first time, he told me he wanted to give a course on various aspects of optical coating. He asked me to take it on as a challenge. We made up what was called a “course” but really wasn’t a course. It involved 2 days with eight different people, spending 2 hours with each person on certain aspects of optical coatings.
Each year it would change a little bit. We would get a different person for pumping or for ion guns or so forth. We did that for several years, until the infamous -88 came along. In San Francisco, Management Plus Inc (MPI) took over, and Vivienne didn’t see it as a course because there were eight people coming to teach it. “How did you pay eight people?” None of us ever got paid anything; we just came and did it.
But Ron Willey and I split the course in half. He chose the optical monitor and coating design, and I took what was left over. It slowly evolved into this materials class that I teach at present. I think he’s still doing optical coating design and optical monitoring.
FZ: About how many times have you taught that course?
DM: Probably about 20 times by now. I would say it’s been about 20 years more or less. It has certainly been taught about 15 times in its current level where the main thrust of the course is how to determine the optical properties of your material after you’ve deposited it.
FZ: So you eventually wound up becoming Program Chair?
DM: Well, I was the TechCon Program Chair for a couple of years.
FZ: How did you come to do it? Don’t you think the Program Chair has a lot of work?
DM: Well I came to it actually because I was the Assistant Program Chair for 2 years. If you are the Assistant Program Chair for 2 years, you come to think you can do it yourself. So, I did it myself for 1 or 2 years, I can’t remember now.
FZ: And then you received the Mentor’s award?
DM: I received an award for the classroom teaching in 2002. That’s when the Society began to recognize mentoring and picked up people who historically had been involved in teaching aspects of optical coating that they felt deserved merit or recognition.
FZ: So if you knew then what you know now, what would you do differently, if anything? What advice could you give people thinking about a career in vacuum coating?
DM: I would say you’ve got to work at it. You have to know your materials; you have to know your design; and you have to go to it and stick to it. Do it because you enjoy it. If you don’t enjoy it, you shouldn’t be doing it!
FZ: Any final statements about the future you would like to share? Do you care to make any predictions?
DM: I won’t do that! I just wish I could see 100 years from now what it is going to be like. Thank you.