Analyzing EM performance during IC manufacturing

摘要

A testing structure, system and method for monitoring electro-migration (EM) performance. A system is described that includes an array of testing structures, wherein each testing structure includes: an EM resistor having four point resistive measurement, wherein a first and second terminals provide current input and a third and fourth terminals provide a voltage measurement; a first transistor coupled to a first terminal of the EM resistor for supplying a test current; the voltage measurement obtained from a pair of switching transistors whose gates are controlled by a selection switch and whose drains are utilized to provide a voltage measurement across the third and fourth terminals. Also included is a decoder for selectively activating the selection switch for one of the array of testing structures; and a pair of outputs for outputting the voltage measurement of a selected testing structure.

主权项

1. A testing structure for monitoring electro-migration (EM) performance, comprising:
an EM resistor having four point resistive measurement, wherein a first and a second terminal of the EM resistor provide current input and a third and a fourth terminal of the EM resistor provide a voltage measurement; a first PFET coupled to the first terminal of the EM resistor as a secondary side of a current mirror for supplying a test current; wherein the voltage measurement is obtained from a pair of switching transistors whose gates are controlled by a selection switch and whose drains are utilized to measure a voltage across the third and fourth terminals; and an inverter and two control PFETs coupled to the first PFET to allow the voltage measurement to be obtained while the first PFET is turned off and the selection switch is activated.