Title :
Measuring the effects of process variations on circuit performance by means of digitally-controllable ring oscillators
Author :
Bassi, A. ; Veggetti, A. ; Croce, L. ; Bogliolo, A.
Author_Institution :
Ferrara Univ., Italy
Abstract :
We present a test chip for the direct measure of the effects of inter/intra-chip process variations on the performance of CMOS circuits. The test structure is a ring oscillator made of modified CMOS inverters that may exhibit two slightly different delays depending on the value of a digital control signal. The incremental delay of each cell is measured from the oscillation periods obtained with different configurations of the control bits. Results are reported for different lots of a 0.18 μm process.
Keywords :
CMOS integrated circuits; delays; integrated circuit testing; integrated circuit yield; logic gates; oscillators; production testing; 0.18 micron; CMOS circuits; cell incremental delay; circuit performance; control bit configurations; delays; digital control signal; digitally-controllable ring oscillators; inter-chip process variations; intra-chip process variations; modified CMOS inverter-based ring oscillator; oscillation periods; process variations effects measurement; test chip; CMOS digital integrated circuits; CMOS process; Circuit optimization; Circuit testing; Digital control; Inverters; Microelectronics; Propagation delay; Ring oscillators; Semiconductor device measurement;
Conference_Titel :
Microelectronic Test Structures, 2003. International Conference on
Print_ISBN :
0-7803-7653-6
DOI :
10.1109/ICMTS.2003.1197464
