Lithography
specialized PZT ceramic interleaved with electrodes. An applied voltage causes a bulk change in the ceramic’s length, allowing the actuators to be used for fast, high-force real-time position control in the nanoscale realm. The solid- state nature of PZT material sets them apart from classical actuators. They require no maintenance or lubricants, and if designed and operated properly, they provide basically unlimited lifetime because there are no parts to wear.
Figure 4. STACIS actuators supporting a photolithography scanner’s isolation platform
26
as well, as its unique hard-mount properties make it compatible with the tool’s existing on-board isolation techniques.
Additionally, smaller form-factor STACIS isolators are now available for use with smaller instrumentation such as SEMs and advanced microscopes outside the semiconductor fab (Figure 5).
The Reliable Heart of STACIS:
Piezo actuators are layered structures of
This and the fact that they solely run on electricity (with zero power required for position hold) greatly reduces operating and facilities costs and addresses thermal drift processes. Their essentially unlimited resolution and high responsiveness and force have made them essential to many classes of instrumentation and production equipment, and recent innovations have broken through traditional travel limitations, providing millimetre travels with sub-nanometre resolution (Figure 9).
In principle and electrical characteristics, piezo actuators resemble ceramic capacitors, and like ceramic capacitors they can be reliable and long lived. In creating STACIS, TMC partnered with PI to incorporate PI piezo actuators which feature unique technologies to extend actuator life significantly beyond traditional benchmarks.
In recent years, PI has invested in its own ceramics factory, PI Ceramic, specifically to drive piezo quality and reliability technologies, since third-party ceramics had been the number-one cause of product failure. Now one of the world’s largest manufacturing facilities for ultra precision
Figure 5. STACIS active isolation is newly available in smaller form-factors for instrumentation such as SEMs
Figure 6. PICMA actuators feature patented all- ceramic encapsulation to significantly increase lifetime in challenging conditions
www.euroasiasemiconductor.com Issue II 2010
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36