Proximity Effect 游明峰

1 What is the proximity effect? 2 Proximity Effect Correction 3 Conclusion 4 Reference Outline

1 What is the proximity effect ? It's due to the scattering of electrons in substrate and resist. Electrons will not only expose the resist at the position they are applied, but also in their long range neighborhood.

Reducing the proximity effect: (a)multilayer resists (b)choosing the resist or substrate thickness (c)increasing the energy of the electrons in the beam (d)step by step exposure of the resist

2 Proximity Effect Correction (a)Dose Modulation:

Double Gaussian+Trail and Error

(b)Pattern biasing A computationally similar approach to dose modulation is pattern biasing.In this approach,the extra dose that dense patterns receive is compensated for by slightly reducing their size.

(c)GHOST

(d) Software

3 Conclusion The advantage of electron beam lithography machines is their ability to produce small feature sizes.But as feature sizes decrease the proximity Effect becomes more and more important. For that reason everybody running an e-beam will see the proximity effect in near future..

4 Reference (1) (2)www,aiss.de/PROXECCO?PROXECCO.html (3)Philip Coane,”Introduction to Electron Beam Lithography”