TEMPTATION
Electron Beam Lithography (EBL) is one of the major methods used for pattern generation in microelectronics. In high throughput EBL, local temperatures during writing can become highly nonuniform, leading to a distortion of the critical dimensions.
The TEMPTATION software predicts resist heating, and can reduce development costs of new technology, or new EBL systems. The classic heat transfer equation cannot be solved for conditions used in EBL. Known models use different simplifications; the results are as different as 14° C and 750° C for equal conditions. Which one is correct? (Probably, neither.)
TEMPTATION uses an advanced analytic model that takes into account all the target layers. The solution is a 13-fold integral. Analytic integration and original algorithms allow for fast numeric simulations. This analytic model does not have a trade-off between speed and accuracy as found in finite elements software.
Experimental verification demonstrated excellent results. All the complicated math is hidden behind a user friendly interface. Our vision is that the engineer should not spend all of his valuable time on learning all the physics – he merely has to insert the parameters of his process and we shall do the rest.
The simulation outputs temperature rises at the required coordinates T(x,y,z,time).
Examples:
T-Pattern

T-patterns are exposed using different flash sizes and sequences of flashes. All other conditions are equal.
Subfield, 32 µm, 50 kV, 1 µm flashes


A subfield is uniformly exposed using a variably shaped beam. The exposure starts at the bottom left corner, moves to the right, and then back up in a serpentine. The time dependent distortions due to heating are predicted and observed experimentally. The temperature dynamics at specified points of the subfield are shown in corresponding colors.
Experimental verification
Simulation of averaged dose over exposure time for this pattern along with its experimental verification is shown below. A great correspondence, is not it?
