Method for measuring thermal differences in infrared emissions from micro devices

• US 5,302,830 A
• Filed: 03/05/1993
• Issued: 04/12/1994
• Est. Priority Date: 03/05/1993
• Status: Expired due to Term

• Current Assignee: General Research Corporation
• Original Assignee: General Research Corporation
• Inventors: Shivanandan, Kandiah
• Primary Examiner(s): FIELDS, CAROLYN
• Application Number:
  US08/026,599
• Time in Patent Office: 403 Days
• Field of Search: 250/342, 250/349, 250/332
• US Class Current: 250/342
• CPC Class Codes: G01J 5/602 using selective, monochromatic or bandpass filtering

Abstract

A method for measuring thermal differences in infrared emissions from semiconductors, the method utilizing an image sensor including an array detector having a plurality of detector elements which produce signals corresponding to semiconductor radiation emission focused thereupon by an optical lens system. At least one bandpass filter is utilized to substantially filter that portion of the semiconductor radiation emission having wavelengths greater than 5 micrometers. The detector element signals are processed to identify performance degrading phenomena occurring in the semiconductor device.

Claims

1. A method of measuring thermal differences in electromagnetic radiation emission from a micro device, comprising the steps of:

placing said micro device within a field of view of an optical lens system;

providing an array detector having a plurality of detector elements;

arranging said optical lens system to focus said electromagnetic radiation emission on said array detector;

filtering said electromagnetic radiation focused on said array detector to substantially eliminate segments of said electromagnetic radiation emission with wavelengths greater than 5 micrometers; and

measuring signals produced by each of said detector elements, said signals respectively corresponding to a portion of said electromagnetic radiation emission focused on each of said detector elements.

2. The method of claim 1, which further comprises the step of modulating said electromagnetic radiation emission to periodically interrupt said electromagnetic radiation emission focused on said array detector.

3. The method of claim 1, wherein said filtering step includes filtering said electromagnetic radiation focused on said array detector to substantially eliminate segments of said electromagnetic radiation emission with wavelengths greater than 5 micrometers and wavelengths less than 3 micrometers.

4. The method of claim 1, wherein said providing step includes providing an array detector selected from a group consisting of indium antimonide, mercury cadmium telluride, and platinum silicide array detectors.

5. The method of claim 4, wherein said arranging step includes arranging an optical lens system having a lens comprised of an optical material selected from a group consisting of zinc selenide, calcium fluoride, and zinc sulfide.

6. The method of claim 4, wherein said micro device is a semiconductor device.

7. The method of claim 4, wherein said micro device is a metal oxide semiconductor field-effect transistor.

8. The method of claim 6, wherein said measuring step includes the step of converting said signals produced by each of said detector elements into numeric data.

9. The method of claim 8, further comprising the step of interpreting said numeric data to detect and locate defects in said semiconductor device.

10. The method of claim 2, wherein said filtering step includes filtering said electromagnetic radiation focused on said array detector to substantially eliminate segments of said electromagnetic radiation emission with wavelengths greater than 5 micrometers and wavelengths less than 3 micrometers.

11. The method of claim 10, wherein said providing step includes providing an array detector selected from a group consisting of indium antimonide, mercury cadmium telluride, and platinum silicide array detectors.

12. The method of claim 11, wherein said arranging step includes arranging an optical lens system having a lens comprised of an optical material selected from a group consisting of zinc selenide, calcium fluoride, and zinc sulfide.

13. The method of claim 11, wherein said micro device is a semiconductor device.

14. The method of claim 11, wherein said micro device is a metal oxide semiconductor field-effect transistor.

15. The method of claim 13, wherein said measuring step includes the step of converting said signals produced by each of said detector elements into numeric data.

16. The method of claim 15, further comprising the step of interpreting said numeric data to detect and locate defects in said semiconductor device.

17. A method of measuring thermal differences in electromagnetic radiation emission from a semiconductor device, comprising the steps of:

placing said semiconductor device within a field of view of an optical lens system;

providing an indium antimonide array detector having a plurality of detector elements;

arranging said optical lens system to focus said electromagnetic radiation emission on said indium antimonide array detector; and

filtering said electromagnetic radiation focused on said indium antimonide array detector to substantially eliminate segments of said electromagnetic radiation emission focused on said indium antimonide array detector with wavelengths greater than 5 micrometers;

modulating said electromagnetic radiation emission to periodically interrupt said electromagnetic radiation emission focused on said indium antimonide array detector; and

measuring signals produced by each of said detector elements, said signals respectively corresponding to a portion of said electromagnetic radiation emission focused on each of said detector elements.

18. The method of claim 17, wherein said filtering step includes filtering said electromagnetic radiation focused on said indium antimonide array detector to substantially eliminate segments of said electromagnetic radiation emission focused on said indium antimonide array detector with wavelengths greater than 5 micrometers and wavelengths less than 3 micrometers.

19. The method of claim 18, wherein said measuring step includes the step of converting said signals produced by each of said detector elements into numeric data.

20. The method of claim 19, further comprising the step of interpreting said numeric data to detect and locate defects in said semiconductor device.