Contactless signal testing

Patent metadata

Field	Value
Publication number	US-9714979-B2
Application number	US-201615243521-A
Country	US
Kind code	B2
Filing date	Aug 22, 2016
Priority date	Dec 3, 2013
Publication date	Jul 25, 2017
Grant date	Jul 25, 2017

Abstract

A method for performing contactless signal testing includes receiving, with a testing pad of an integrated circuit, a signal within a beam. The method further includes converting, with a number of diodes connected to a positive voltage supply, an electrical current signal created by the electron beam to a voltage signal, wherein the number of diodes includes a diode stack of multiple diodes. The method further includes extracting, with a digital inverter, a test signal from the voltage signal.

First claim

What is claimed is:

1. A method for performing contactless signal testing, the method comprising:
receiving, with a testing pad of an integrated circuit, a signal within a beam;
converting, with a number of diodes connected to a positive voltage supply, an electrical current signal created by the beam to a voltage signal, wherein the number of diodes includes a diode stack of multiple diodes; and
extracting, with a digital inverter, a test signal from the voltage signal.

2. The method of claim 1 , wherein a frequency of the signal is set by an on and off period of the beam.

3. The method of claim 1 , wherein the number of diodes in the diode stack of multiple diodes is within a range of 3-6.

4. The method of claim 1 , wherein the testing pad corresponds to a bonding pad.

5. The method of claim 1 , further comprising, with a number of additional testing pads on the integrated circuit, receiving a number of additional independent signals.

6. The method of claim 5 , wherein a total number of testing pads on the integrated circuit is less than a total number of bonding pads.

7. The method of claim 1 , wherein the test signal is a time-division multiplexed signal.

8. The method of claim 7 , further comprising, temporarily storing the time-division multiplexed signal in a memory of the integrated circuit.

9. The method of claim 8 , further comprising, de-multiplexing the multiplexed signal with a de-multiplexing circuit of the integrated circuit before passing the test signal to the digital circuitry.

10. The method of claim 1 , wherein the testing pad is within a size range of about 0.80-1.20 square micrometers.

11. An integrated circuit device having contactless testing capability, the integrated circuit comprising:
a testing pad to receive a beam having a signal embedded therein;
a number of diodes connected between the testing pad and a positive voltage supply, the diodes to convert an electric current induced by the beam to a voltage, wherein the number of diodes includes a diode stack of multiple diodes; and
a digital circuit component to extract a digital test signal from the signal based on a voltage level of the number of diodes.

12. The integrated circuit device of claim 11 , wherein the testing pad is also a bonding pad.

13. The integrated circuit device of claim 11 , wherein the testing pad is separate from a bonding pad and the testing pad and bonding pad connect to the same circuit path within the integrated circuit.

14. The integrated circuit device of claim 11 , wherein the number of diodes in the diode stack having a number of diodes within a range of 3 and 6.

15. The integrated circuit device of claim 11 , further comprising additional testing pads, each of the additional testing pads corresponding to one of a multiple of bonding pads.

16. The integrated circuit device of claim 11 , further comprising:
a memory to temporarily store a time-division multiplexed signal; and
a de-multiplexer to de-multiplex a signal stored in the memory.

17. The integrated circuit device of claim 11 , wherein the testing pad is within a size range of about 0.80-1.20 square micrometers.

18. An integrated circuit device having contactless testing capability, the integrated circuit comprising:
a testing pad comprising a number of photo-sensitive devices that produce an electric current in response to an optical beam;
a current-to-voltage structure to convert the electric current from the photo-sensitive devices to a voltage, the current-to-voltage structure comprising a diode stack of multiple diodes; and
a digital circuit component to extract a digital test signal embedded in the optical beam.

19. The integrated circuit device of claim 18 , wherein the testing pad corresponds to a bonding pad of the integrated circuit.

20. The integrated circuit device of claim 18 , further comprising:
a memory to temporarily store a time-division multiplexed signal embedded within the optical beam; and
a de-multiplexer to de-multiplex the time-division multiplexed signal stored in the memory.

Assignees

• Taiwan Semiconductor Mfg Co Ltd

Inventors

• Huang Bo-Jr
• Tseng Nan-Hsin
• Liu Yen-Ling

Classifications

• G01R31/3025

  Wireless interface with the DUT · CPC title

• G01R1/07

  Non contact-making probes · CPC title

• G01R31/307 Primary

  of integrated circuits · CPC title