• Explore Membership
  • Student Services
  • Student Events
    Student Chapters
    MKS Instruments Awards
    Student Author Travel Grants
    Visiting Lecturers
    Lecturer Directory
    Travel Policies
  • Early Career Resources
  • Corporate Membership
  • SPIE Professional Magazine
Print PageEmail Page

Chris A. Mack

Dr. Chris A. Mack


1605 Watchhill Rd.

Austin TX 74703
United States

tel: 512 322 0980
E-mail: chris@lithoguru.com

Area of Expertise

Semiconductor lithography


Dr. Chris A. Mack received Bachelor of Science degrees in physics, chemistry, electrical engineering, and chemical engineering from Rose-Hulman Institute of Technology in 1982, a Master of Science degree in electrical engineering from the University of Maryland in 1989, and a Ph.D. in chemical engineering from the University of Texas at Austin in 1998. Dr. Mack founded FINLE Technologies in 1990, serving as President and Chief Technical Officer until the acquisition of FINLE by KLA-Tencor in 2000. For the next five years he served as Vice President of Lithography Technology for KLA-Tencor. Currently, he writes, teaches and consults in the field of semiconductor lithography. He is also an adjunct faculty member at the University of Texas at Austin. In 2003 he received the SEMI Award for North America.

Lecture Title(s)

The New, New Limits of Optical Lithography
The end of optical lithography has been so often predicted (incorrectly) that such predictions are now a running joke among lithographers. Yet optical lithography does have real, physical limitations and even more real economic limits, and an accurate estimation of these limits is essential for planning potential next generation lithography (NGL) efforts. In this paper I'll review the two types of resolution limits in optical lithography: the pitch resolution, governed by the amount of spatial frequency information that can pass through an imaging lens, and the feature size resolution, limited by our ability to control feature size. Projecting the trends in these resolution limits, the capabilities of 193nm immersion lithography will be explored. It will be shown that 45nm half pitches and 32nm feature sizes are certainly possible and in fact likely with 193nm immersion. A half-pitch of 40nm is near the limit of 193nm immersion, but the cut-off of feature size is less sharp and 25nm features may be possible. Thus, optical lithography is likely to defy Sturtevant's Law (the end of optical lithography is always 6-7 years out) and push far into the next decade.

Exploring the Capabilities of Immersion Lithography
Immersion lithography has recently emerged as an interesting potential candidate for extending 193nm lithography to the 45nm lithography node and beyond. By immersing the wafer in a high index fluid the numerical aperture (NA) of the lens can be made higher by a factor of the refractive index of the fluid. Numerical apertures as high as 1.3 are certainly possible. While such a high numerical aperture is normally accompanied by an extreme decrease in the depth of focus at the resolution limit, an advantage of the immersion approach to increasing the numerical aperture is that the depth of focus is increased by a factor of the refractive index, mitigating some of the DOF loss due to the higher NA. Though this technique for resolution enhancement is receiving significant attention, useful experimental data on the subtle effects of such high NA imaging is one to two years away. Thus, simulation is expected to bridge the gap in immersion lithography research.

The End of the Semiconductor Industry as We Know It
Continued migration down the path predicted by Moore's Law must eventual come to an end. The goal of this presentation is to discuss the technical and economic drivers of Moore's Law, with special emphasis on their interdependence. These drivers can be classified as "push" (technology improvements push us down the Moore's Law path) and "pull" (the economic incentives create increasing chip production volumes which drive the technology learning curve). In fact, Moore's Law can be considered as an instance of general learning curve theory, which places a special importance on the role of increasing chip volumes on the slope of Moore's Law. After a general discussion of the macro-trends of the semiconductor industry, developments in optical lithography are described in relation to the growth of the semiconductor industry. The economics of the semiconductor industry, and thus optical lithography, is discussed and its impact on technology development explained. When, if ever, will optical lithography be supplanted by the next leap in lithography technology? What are the economic impacts of the end of Moore's Law? When will the author's career come to a crashing halt? All of these questions and more will be answered.

Ready for the benefits of individual SPIE membership?
Join or Renew
Already a member? Get access to member-only content.
Sign In

Member-only Content:

These articles are available only to SPIE Members as a valuable resource.
Member-only content Icon
Icon denotes member-only content.

The Joe and Agnete Yaver Memorial Scholarship

SPIE Online Courses

At Your Pace - On Your Schedule

SPIE t-shirts, ties, and scarves are now available. Get free shipping for a limited time. Shop now.

2018 Salary Report