Method and system for measuring radiation and temperature exposure of wafers along a fabrication process line

Patent metadata

Field	Value
Publication number	US-9823121-B2
Application number	US-201514880899-A
Country	US
Kind code	B2
Filing date	Oct 12, 2015
Priority date	Oct 14, 2014
Publication date	Nov 21, 2017
Grant date	Nov 21, 2017

Abstract

A measurement wafer device for measuring radiation intensity and temperature includes a wafer assembly including one or more cavities. The measurement wafer device further includes a detector assembly. The detector assembly is disposed within the one or more cavities of the wafer assembly. The detector assembly includes one or more light sensors. The detector assembly is further configured to perform a direct or indirect measurement of the intensity of ultraviolet light incident on a surface of the wafer assembly. The detector assembly is further configured to determine a temperature of one or more portions of the wafer assembly based on one or more characteristics of the one or more light sensors.

First claim

What is claimed:

1. A measurement wafer apparatus for measuring radiation intensity and temperature comprising:
a wafer assembly including one or more cavities; and
a detector assembly, at least a portion of the detector assembly disposed within the one or more cavities of the wafer assembly, the detector assembly including one or more light sensors, the detector assembly configured to perform at least one of a direct measurement of the intensity of ultraviolet light from a process environment incident on at least one surface of the wafer assembly or an indirect measurement of the intensity of ultraviolet light from the process environment incident on the at least one surface of the wafer assembly, wherein the detector assembly is further configured to determine a temperature of one or more portions of the wafer assembly based on one or more characteristics of the one or more light sensors upon measuring the intensity of the ultraviolet light from the process environment incident on the at least one surface of the wafer assembly.

2. The apparatus of claim 1 , wherein the wafer assembly comprises:
a substrate; and
a cover operably coupled to a portion of the substrate.

3. The apparatus of claim 1 , wherein the detector assembly includes:
one or more photoluminescent elements configured to convert ultraviolet light to visible light, wherein the one or more light sensors are configured to perform an indirect measurement of the intensity of ultraviolet light incident on the one or more photoluminescent elements by measuring the intensity of visible light emitted by the one or more photoluminescent elements.

4. The apparatus of claim 3 , wherein the detector assembly includes:
one or more light guiding elements disposed within the one or more cavities, wherein the one or more light guiding elements are configured to transmit visible light emitted by the one or more photoluminescence elements to the one or more light sensors.

5. The apparatus of claim 1 , wherein the one or more light sensors are configured to perform a direct measurement of the intensity of ultraviolet light incident on the one or more light sensors.

6. The apparatus of claim 1 , wherein the one or more characteristics of the one or more light sensors comprise:
at least one of an electrical characteristic or an intensity characteristic of the one or more light sensors.

7. The apparatus of claim 6 , wherein the electrical characteristic comprises:
a forward voltage across the one or more light sensors measured at a known current.

8. The apparatus of claim 6 , wherein the intensity characteristic comprises:
an intensity characteristic of visible light incident on the one or more light sensors in response to the excitation of one or more photoluminescence elements by the ultraviolet light.

9. The apparatus of claim 1 , wherein the detector assembly comprises:
a local controller configured to receive one or more signals from the one or more light sensors indicative of at least one of the intensity of ultraviolet light incident on at least one of the one or more light sensors or one or more photoluminescent elements or an electrical characteristic of the one or more light sensors; and
a central controller communicatively coupled to the local controller and configured to determine a temperature of the one or more portions of the wafer assembly based on at least one of the intensity of ultraviolet light incident on at least one of the one or more light sensors or one or more photoluminescent elements or an electrical characteristic of the one or more light sensors.

10. The apparatus of claim 1 , wherein the wafer assembly includes one or more openings at the at least one surface of the wafer assembly configured to pass ultraviolet light incident on the at least one surface of the wafer assembly to the one or more light sensors of the detector assembly.

11. The apparatus of claim 10 , wherein the wafer assembly includes one or more windows positioned at the one or more openings at the at least one surface of the wafer assembly and configured to transmit ultraviolet light incident on the at least one surface of the wafer assembly to the one or more light sensors of the detector assembly.

12. The apparatus of claim 11 , wherein the wafer assembly includes one or more entrance filters disposed at least proximate to the one or more windows and configured to block a selected portion of light incident on the at least one surface of the wafer assembly.

13. The apparatus of claim 1 , wherein the one or more light sensors comprise:
one or more diode detectors.

14. The apparatus of claim 13 , wherein the one or more diode detectors comprise:
at least one of a silicon carbide detector, gallium nitride diode detector, aluminum gallium nitride detector or a silicon detector.

15. The apparatus of claim 14 , wherein the one or more light sensors and the one or more local controllers are disposed within the cavity between the substrate and the cover.

16. A measurement wafer apparatus for measuring radiation intensity and temperature comprising:
a wafer assembly including one or more cavities; and
a detector assembly, at least a portion of the detector assembly disposed within the one or more cavities of the wafer assembly, the detector assembly including one or more light sensors, the detector assembly configured to perform at least one of a direct measurement of the intensity of ultraviolet light from a process environment incident on at least one surface of the wafer assembly or an indirect measurement of the intensity of ultraviolet light from the process environment incident on the at least one surface of the wafer assembly, wherein the detector assembly is further configured to determine a temperature of one or more portions of the wafer assembly based on at least one of one or more characteristics of the one or more light sensors or one or more temperature measurements from one or more temperature sensors disposed at least proximate to the one or more light sensors.

17. A measurement wafer apparatus for measuring radiation intensity and temperature comprising:
a substrate;
a cover operably coupled to a portion of the substrate;
one or more cavities formed between the substrate and the cover;
a detector assembly including one or more light sensors disposed within the one or more cavities, wherein the cover includes one or more openings for passing light to the one or more light sensors from a top surface of the cover, wherein the one or more light sensors are configured to measure the intensity of light from a process environment passed through the one or more openings; and
one or more local controllers communicatively coupled to the one or more light sensors, the one or more local controllers configured to receive one or more signals indicative of at least one of the intensity of light measured by the one or more light sensors or one or more additional characteristics of the one or more light sensors.

18. The apparatus of claim 17 , wherein the one or more light sensors are configured to directly measure the intensity of light passed through the one or more openings.

19. The apparatus of claim 17 , further comprising:
one or more central controllers communicatively coupled to the one or more local controllers and configured to determine the temperature of the one or more light sensors based on the one or more additional characteristics of the one or more light sensors.

20. The apparatus of claim 19 , wherein the one or more additional characterist

Assignees

• Kla Tencor Corp

Inventors

• Sun Mei
• Jensen Earl
• O'Brien Kevin

Classifications

• H10P74/20

  characterised by the properties tested or measured, e.g. structural or electrical properties · CPC title

• H10P72/0604

  Process monitoring, e.g. flow or thickness monitoring · CPC title

• H10P72/0602 Primary

  Temperature monitoring · CPC title

• G01J5/10

  using electric radiation detectors · CPC title

• G01J5/0818

  Waveguides · CPC title