Decoupled flux control for molecular beam epitaxy

Author

Garrett, Patrick H. ; Heyob, Jeffrey J. ; Hunt, Victor J. ; LeClair, Steven R. ; Patterson, Oliver D.

Author_Institution

Dept. of Electr. & Comput. Eng., Cincinnati Univ., OH, USA

Volume

6

Issue

4

fYear

1993

fDate

11/1/1993 12:00:00 AM

Firstpage

348

Lastpage

356

Abstract

Improvement of the manufacturing capability for the molecular beam epitaxy (MBE) process is demonstrated with respect to the consistent achievement of effusion cell flux stability of 1% of setpoint values. This performance was obtained by decoupling the principal sources of flux variability from each cell temperature control system including: cell shutter opening flux disturbances with implementation of a feedforward compensator that precisely cancels evaporant mass enthalpy transients; electric power frequency-correlation flux disturbances with substitution of heater DC drivers for the standard AC triac drivers; and flux process disorder resulting from coupled temperature controller proportional-integral-derivative (PID) tuning values with identification of decoupled trapezoidal PID tuning values

Keywords

molecular beam epitaxial growth; process control; semiconductor device manufacture; semiconductor epitaxial layers; semiconductor growth; temperature control; three-term control; PID tuning; cell shutter opening flux disturbances; cell temperature control system; coupled temperature controller; effusion cell flux stability; electric power frequency-correlation flux disturbances; feedforward compensator; flux process disorder; flux variability; heater DC drivers; manufacturing capability; mass enthalpy transients; molecular beam epitaxy; setpoint values; Frequency; Manufacturing processes; Molecular beam epitaxial growth; Pi control; Stability; Temperature control; Three-term control; Thyristors; Tuning; Weight control;

fLanguage

English

Journal_Title

Semiconductor Manufacturing, IEEE Transactions on

Publisher

ieee

ISSN

0894-6507

Type

jour

DOI

10.1109/66.267645

Filename

267645