Lambda Physik looks bright at 25

The nitrogen laser that launched Lambda Physik (Göttingen, Germany) 25 years ago was displayed at CLEO/QELS `97 (Baltimore, MD) last month in honor of the company`s 25th anniversary. That laser will join its cousin, the first commercial excimer laser, in a larger Lambda Physik display at Laser 97 in Munich, Germany, later this month (see p. 15).

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Lambda Physik looks bright at 25

Laurie Ann Peach, Assistant Editor, Technology

The nitrogen laser that launched Lambda Physik (Göttingen, Germany) 25 years ago was displayed at CLEO/QELS `97 (Baltimore, MD) last month in honor of the company`s 25th anniversary. That laser will join its cousin, the first commercial excimer laser, in a larger Lambda Physik display at Laser 97 in Munich, Germany, later this month (see p. 15).

In 1971, two German chemistry doctoral students, Dirk Basting and Bernd Steyer, developed the nitrogen laser and donated it to the Max Planck Institut (Göttingen, Germany), where they were studying. The nitrogen laser was born out of necessity, says Basting. The only lasers available at the time were either too expensive--selling for $50,000 to $60,000 a piece--or they did not generate the power required by the researchers. Recognizing the value of the students` invention, Carl Zeiss (Oberkochen, Germany) bought their next laser for $10,000, applied for a patent, paid all filing expenses, then transferred the patent to Basting and his partner free of charge. "The rest was u¥to us," says Basting, now president and CEO of Lambda Physik (see photos).

In just a quarter of a century, Lambda Physik has grown from a two-person venture in Basting`s den into a $50+ million company, employing 250 people worldwide. And the future looks bright. "The company did not start out as a typical business," says Basting. "It really was driven by customer demand." Last fall, the company opened a new office in the United States, in Fort Lauderdale, FL. During the first six months of operation, says Basting, "we`ve doubled our bookings for excimer applications." In addition, record results were reported for the first half of FY1997, ended March 31, 1997.

Excimers take the lead

Although the nitrogen laser was responsible for the company`s start up, it is the excimer laser that has made the firm a major player within the industry. When excimer lasers were developed in the late 1970s, says Basting," it seemed natural that [Lambda Physik] would lead the market for a number of reasons." First, the pulsed gas laser technology was similar to that of the nitrogen laser. Second, the company was in an excellent location, near a source of the high-quality fluorine required for laser gases. Third, because of their chemical background, Basting and Steyer understood the material processes involved when working with corrosive gases. Lambda Physik offered the first commercial excimer laser in 1977, the EMG500.

The excimer laser`s industrial potential is just now being realized. "It is an interesting phenomenon how long technology takes to be utilized," says Basting. In the beginning, the excimer laser was used primarily for laboratory research where there was a strong interest in a high-powered UV source. "There was, and is, no other light source in this wavelength range," says Basting.

Commercial interest did not pick u¥until 1983 when Dr. R. Srinivasan, then at IBM Research, began using excimer lasers during his pioneering work on photoablation for eye surgery. An industrial revolution for excimer lasers sprang from his work, says Basting. Today krypton fluoride lasers are critical to the semiconductor-processing industry, for the annealing of the silicon used in flat-panel displays, and for ink-jet printer cartridge fabrication. Novel applications continue to be developed.

"We are already developing the next generation of shorter-wavelength argon fluoride excimers for microlithog raphy," says Basting. "By the end of this decade, argon fluoride lasers will be the light source of choice to produce ultrahigh-density ICs with sub-quarter-micron feature sizes."

"There are people who think excimer lasers are dangerous and will soon be replaced by solid-state [devices]," Basting says. "However, there is no other light source that can get down into the UV--from 350 to 157 nm--with as much power. One can frequency-double or -triple the output of visible or near-IR light sources, but these nonlinear techniques are not easily scalable to high power. There is a lot of research in solid state to show they can produce UV [light], but it is all experimental."

Two years ago, Lambda began work on a diode-pumped Nd:YAG laser aimed at producing UV light by frequency conversion. The device was to complement the excimer laser at the lower end of the range. "We did this because it is difficult to take a high-powered excimer laser and try to scale it down. But solid state is the other way around--one starts small and scales up," says Basting.

The resulting laser was the StarLine. "But even this only produces several watts of UV at peak power, compared to several hundred watts available from commercial excimer lasers," says Basting. "The StarLine will be a great complementary solution, when high-powered UV isn`t required. But most industrial sources today need high power and there is no way to achieve this with solid state."

"There is strong growth for excimer lasers in all wavelengths and areas for years to come," says Basting. "Some markets are just now beginning to develo¥a huge potential for the lasers. I am excited about the excimer`s future."

In the early 1980s, Coherent (Santa Clara, CA) and Spectra Physics (Mountain View, CA) became interested in Lambda Physik. In 1981, when Basting`s partner moved on, Coherent acquired Steyer`s shares and now owns an 80% interest in the company.

According to the calendar, Lambda Physik turned 25 in 1996, but because the company was so busy with orders, it decided to celebrate the event during the fiscal year instead. "Interestingly, our 25th anniversary coincides with the 25th anniversary of the Max Planck Institut where I got my education," Basting says proudly.

Looking toward the future

As Lambda Physik`s first 25 years were driven by technological advances, the company hope to continue this trend through internal developments and strategic alliances with other companies. For example, through cooperation with Ultratech Stepper (Santa Clara, CA), Lambda manufactured a specific excimer laser for a proprietary semiconductor manufacturing process. Lambda`s plant in Florida includes a research and development department to facilitate closer partnerships with the research infrastructure in this country.

Looking back, Basting tells the story of when the fledgling partners tried to obtain a state business license. When the inspector came, he and Steyer offered him tea spiced u¥with a bit of rum, as was the local custom. As they began to demonstrate the prototype nitrogen laser, the power supply immediately short-circuited with a loud bang, startling the students and inspector. Basting and Steyer offered to fix the unit and try again, but the inspector said that wasn`t necessary and left. The two thought it was all over, but they received their license anyway and Lambda Physik was born. "Maybe the tea helped with his decision," Basting says. o

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Lambda Physik cofounder Dirk Basting (left) was codeveloper, in 1971, of the nitrogen laser that launched a new company (above).

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