Title :
Circuit for monitoring BJT RF performance using DC measurements
Author :
Fox, Robert M. ; Chawla, R. ; Eisenstadt, W.R. ; Hemmenway, D. ; Johnston, J.
Author_Institution :
Dept. of Electr. & Comput. Eng., Florida Univ., Gainesville, FL, USA
fDate :
9/1/2002 12:00:00 AM
Abstract :
A test circuit is described for on-wafer monitoring of high-frequency performance of bipolar junction transistors 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 transistors´ 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 :
BiCMOS analogue integrated circuits; Monte Carlo methods; circuit simulation; frequency measurement; microwave bipolar transistors; microwave oscillators; process monitoring; semiconductor device measurement; semiconductor device testing; 3 GHz; BJT RF performance; BiCMOS technology; DC measurements; IC process development; Monte Carlo simulations; bipolar junction transistors; correlation coefficient; high-frequency oscillator; high-frequency performance; layout variations; maximum oscillation frequency; minimum bias current for oscillation; on-wafer monitoring; oscillation-amplitude detector; process variations; test monitoring circuit; Bipolar transistor circuits; Capacitance; Circuit testing; Detectors; Fluid flow measurement; Inductors; Monitoring; Oscillators; Radio frequency; Semiconductor device measurement;
Journal_Title :
Solid-State Circuits, IEEE Journal of
DOI :
10.1109/JSSC.2002.801203
