Screening of semiconductor integrated circuit devices

A method of screening semiconductor integrated circuit devices, comprising the steps of:

• (a) supplying a specific power supply voltage to semiconductor integrated circuit devices to be tested while applying a specific test signal to the devices at a specific period;
• (b) observing power supply currents of the devices caused by the power supply voltage and the test signal,
• (c) generating sets of power spectrum data of the power supply currents of the devices corresponding to the test signal;
• (d) generating distributions of the sets of power spectrum data of the power supply currents before a burn-in test;
• (e) performing the steps (a) to (d) while performing a burn-in test for the devices after the step (d), generating distributions of the sets of power spectrum data of the power supply currents during the burn-in test;
• (f) performing the steps (a) to (d) after the burn-in test is completed in the step (e), generating distributions of the sets of power spectrum data of the power supply currents after the burn-in test,
• (g) generating distribution change rates of power spectrum data of the power supply currents based on the distributions of the sets of power spectrum data of the power supply currents obtained in the steps (d), (e), and (f);
• and
• (h) judging whether or not the distribution change rates of power spectrum data of the power supply currants generated in the step (g) are equal to or greater than a specific reference value;
• wherein when the distribution change rate of power spectrum data of the power supply current of one of the devices is equal to or greater than the reference value, the device in question is regarded as a faulty one.

An apparatus for screening semiconductor integrated circuit devices, comprising:

• (a) a test power supply for generating a power supply voltage applied to semiconductor integrated circuit devices to be tested;
• (b) a test signal generator for generating a test signal supplied to the devices;
• (c) a spectrum analyzer for observing power supply currents of the devices caused by the power supply voltage and the test signal and for generating sets of power spectrum data of the power supply currents of the devices corresponding to the test signal;
• (d) a data storage for storing the sets of power spectrum data of the power supply currents of the devices;
• and
• (e) a data analyzer for generating distributions of the sets of power spectrum data of the power supply currents and for judging whether or not the distributions of the sets of power spectrum data of the power supply currents are equal to or greater than a specific reference value;
• wherein when the distribution of the set of power spectrum data of the power supply current of one of the devices is equal to or greater than the reference value, the device in question is regarded as a faulty one.

A computer program product having a computer readable medium and a computer program recorded thereon, the computer program being operable to screen semiconductor integrated circuit devices;

• the product comprising:
• (a) code that supplies a specific power supply voltage to semiconductor integrated circuit devices to be tested while applying a specific test signal to the devices at a specific period;
• (b) code that observes power supply currents of the devices caused by the power supply voltage and the test signal;
• (c) code that generates sets of power spectrum data of the power supply currents of the devices corresponding to the test signal;
• (d) code that generates distributions of the sets of power spectrum data of the power supply currents;
• and
• (e) code that judges whether or not the distributions of the sets of power spectrum data of the power supply currents are equal to or greater than a specific reference value:
• wherein when the distribution of the set of power spectrum data of the power supply current of one of the devices is equal to or greater than the reference value, the device in question is regarded as a faulty one.

A computer program product having a computer readable medium and a computer program recorded thereon, the computer program being operable to screen semiconductor integrated circuit devices;

• the product comprising:
• (a) code that supplies a specific power supply voltage to semiconductor integrated circuit devices to be tested while applying a specific test signal to the devices at a specific period;
• (b) code that observes power supply currents of the devices caused by the power supply voltage and the test signal;
• (c) code that generates sets of power spectrum data of the power supply currents of the devices corresponding to the test signal;
• (d) code that generates distributions of the sets of power spectrum data of the power supply currents before a burn-in test;
• (e) code that performs the steps (a) to (d) while performing a burn-in test for the devices after the step (d), generating distributions of the sets of power spectrum data of the power supply currents during the burn-in test;
• (f) code that performs the steps (a) to (d) after the burn-in test is completed in the step (e), generating distributions of the sets of power spectrum data of the power supply currents after the burn-in test;
• (g) code that generates distribution change rates of power spectrum data of the power supply currents based on the distributions of the sets of power spectrum data of the power supply currents obtained in the steps (d), (e), and (f);
• and
• (h) code that judges whether or not the distribution change rates of power spectrum data of the power supply currents generated in the step (g) are equal to or greater than a specific reference value;
• wherein when the distribution change rate of power spectrum data of the power supply current of one of the devices is equal to or greater than the reference value, the device in question is regarded as a faulty one.