US 2003/0193051 A1 · Measuring junction leakage

Abstract

A test structure is provided for allowing a parametric test system, for example towards the end of a production line at a foundry, to measure the junction leakage of a semiconductor device such as an integrated circuit. The structure is formed as part of the device and comprises a MOSFET whose source and drain are provided with connections which are accessible to the tester for biasing the device and measuring the drain current. A capacitor is connected between the gate of the MOSFET and another connection allowing the tester to supply various voltages to the connection. A junction diode is connected between the gate and body terminal of the MOSFET. During testing, the parametric tester supplies a voltage to allow the capacitor 1 to be charged via the forward-biased diode. The tester then supplies another voltage such that the diode becomes reverse-biased and its leakage current discharges the capacitor so that the voltage on the gate of the MOSFET falls. The drain current thus falls and the junction leakage through the diode can be determined from the rate of change of the drain current and knowledge of the transfer characteristic of the MOSFET and the capacitance of the capacitor.

Claims13

Dependent claims

A test structure for permitting a measurement of a junction leakage of a semiconductor device, comprising:

a first metal oxide semiconductor field effect transistor having a drain, which is accessible to permit a drain current to be measured, a source and a gate;
a junction diode having a first terminal, which is connected to said gate of said first transistor, and a first capacitor having a first terminal connected to said gate of said first transistor and a second terminal which is accessible to permit a voltage thereon to be selected.

A method of measuring a junction leakage of a semiconductor device comprising a test structure for permitting a measurement of a junction leakage of a semiconductor device, comprising:

a first metal oxide semiconductor field effect transistor having a drain, which is accessible to permit a drain current to be measured, a source and a gate;
a junction diode having a first terminal, which is connected to said gate of said first transistor, and a first capacitor having a first terminal connected to said gate of said first transistor and a second terminal which is accessible to permit a voltage thereon to be selected, said method comprising the steps of:
connecting said second terminal of said first capacitor to a first voltage for forward-biasing said diode so as to charge said first capacitor;
connecting said second terminal of said first capacitor to a second voltage such that said diode is reverse-biased;
and
determining said junction leakage from a rate of change of said drain current.

3 more elements

Dependencies are inferred from the claim text.

Measuring junction leakage

Life of this patent

Measuring junction leakage

Life of this patent

Abstract

Claims13