Title :
Circuit for monitoring BJT RF performance using DC measurements
Author :
Fox, R.M. ; Chawla, R. ; Eisenstadt, W.R. ; Hemmenway, D. ; Johnston, J.
Author_Institution :
Dept. of Electr. & Comput. Eng., Florida Univ., Gainesville, FL, USA
fDate :
6/23/1905 12:00:00 AM
Abstract :
A test circuit is described for on-wafer monitoring of high-frequency performance of bipolar junction transistors (BJTs) using only DC measurements. The test circuit includes an oscillation-amplitude detector and a high-frequency (~3 GHz) oscillator whose minimum bias current for oscillation (Iosc) correlates strongly with the transistor maximum oscillation frequency (fmax). Variations in the circuit´s Iosc can be routinely monitored to track changes in fmax caused by process variations. Monte Carlo simulations showed a correlation coefficient of -0.79 between Iosc and fmax. Variations in measured fmax intentionally introduced through layout variations were verified to be strongly correlated with Iosc
Keywords :
Monte Carlo methods; bipolar transistors; microwave bipolar transistors; microwave measurement; microwave oscillators; semiconductor device testing; 3 GHz; BJT; Colpitts oscillator; DC measurements; Monte Carlo simulations; RF performance monitoring; correlation coefficient; high-frequency oscillator; high-frequency performance; layout variations; maximum oscillation frequency; minimum bias current for oscillation; on-wafer monitoring; oscillation-amplitude detector; test circuit; Capacitance; Capacitors; Circuit testing; Computerized monitoring; Equivalent circuits; Frequency measurement; Gain measurement; Inductors; Oscillators; Radio frequency;
Conference_Titel :
Bipolar/BiCMOS Circuits and Technology Meeting, Proceedings of the 2001
Conference_Location :
Minneapolis, MN
Print_ISBN :
0-7803-7019-8
DOI :
10.1109/BIPOL.2001.957876
