Methods and apparatus to determine parameters in metal-containing films

Patent metadata

Field	Value
Publication number	US-9880233-B2
Application number	US-201113095279-A
Country	US
Kind code	B2
Filing date	Apr 27, 2011
Priority date	Apr 27, 2011
Publication date	Jan 30, 2018
Grant date	Jan 30, 2018

Abstract

A method and apparatus to determine a parameter of a metal-containing film are provided herein. In some embodiments, a method of determining a parameter of a metal-containing film may include generating a first magnetic field by flowing an alternating current through a coil disposed adjacent to and spaced apart from the metal-containing film, wherein the first magnetic field induces a second magnetic field proximate the metal-containing film; heating the metal-containing film from a first temperature to a second temperature; measuring a response of the first magnetic field to the second magnetic field as the metal-containing film is heated from the first temperature to the second temperature; and correlating the response with a rate of temperature change of the metal-containing film as the metal-containing film is heated from the first temperature to the second temperature to determine a parameter of the metal-containing film.

First claim

The invention claimed is:

1. A method of determining a parameter of a metal-containing film, comprising:
generating a first magnetic field by flowing an alternating current through a coil disposed adjacent to and spaced apart from the metal-containing film, wherein the first magnetic field induces a second magnetic field proximate the metal-containing film;
heating the metal-containing film from a first temperature to a second temperature;
measuring the temperature of the metal-containing film at a plurality of times over a time period as the metal-containing film is heated from the first temperature to the second temperature;
determining a rate of temperature change based on the measured temperature;
measuring a response of the first magnetic field to the second magnetic field as the metal-containing film is heated from the first temperature to the second temperature; and
correlating the response with the rate of temperature change of the metal-containing film as the metal-containing film is heated from the first temperature to the second temperature to determine a thickness of the metal-containing film.

2. The method of claim 1 , wherein the second magnetic field opposes the first magnetic field.

3. The method of claim 1 , wherein an induced current in the metal-containing film flows about a surface of the metal-containing film in an opposing direction to the alternating current of the coil.

4. The method of claim 3 , wherein the induced current changes as a function of the temperature of the metal-containing film.

5. The method of claim 1 , wherein heating the metal-containing film further comprises:
delivering a known quantity of energy to the metal-containing film.

6. The method of claim 5 , wherein heating the metal-containing film further comprises:
heating the metal-containing film with a light source.

7. The method of claim 6 , wherein the light source illuminates a surface aligned with the coil and wherein a diameter of the surface illuminated by the light source is substantially equivalent to a diameter of the coil.

8. The method of claim 5 , wherein heating the metal-containing film further comprises:
heating the metal-containing film with a heating element by flowing a current through the heating element, wherein the flow of the alternating current through the coil is alternated with the flow of the current through the heating element.

9. The method of claim 1 , wherein measuring the response of the first magnetic field further comprises:
measuring at least one of impedance or resonance frequency of the alternating current through the coil.

10. The method of claim 9 , further comprising:
determining a resistivity of the metal-containing film from at least one of the measured impedance or the measured resonance frequency.

11. The method of claim 1 , wherein measuring the response of the first magnetic field further comprises:
measuring the response at a plurality of times over a time period as the metal-containing film is heated from the first temperature to the second temperature.

12. A method of determining a parameter of a metal-containing film, comprising:
generating a first magnetic field by flowing an alternating current through a coil disposed adjacent to and spaced apart from the metal-containing film, wherein the first magnetic field induces a second magnetic field proximate the metal-containing film;
heating the metal-containing film from a first temperature to a second temperature;
modeling the temperature of the metal-containing film over a time period based on an amount of energy provided to heat the metal-containing film from the first temperature to the second temperature;
determining a rate of temperature change based on the modeled temperature;
measuring a response of the first magnetic field to the second magnetic field as the metal-containing film is heated from the first temperature to the second temperature; and
correlating the response with the rate of temperature change of the metal-containing film as the metal-containing film is heated from the first temperature to the second temperature to determine a thickness of the metal-containing film.

13. The method of claim 1 , wherein the time period begins when the metal-containing film is at the first temperature and ends when the metal-containing film is at the second temperature.

14. The method of claim 1 , wherein the metal-containing film further includes a metal layer disposed atop a barrier layer.

15. The method of claim 14 , wherein the second magnetic field results from an induced response in both the metal layer and the barrier layer and wherein the rate of change in the temperature of the metal-containing film results from heating both the metal layer and the barrier layer.

16. The method of claim 15 , wherein a ratio of a thickness of the metal layer to a thickness of the barrier layer is correlated with the response with the rate of temperature change of the metal-containing film as the metal-containing film is heated from the first temperature to the second temperature.

17. A system for determining a parameter of a metal-containing film disposed on a substrate, comprising:
a substrate support to support a substrate comprising the metal-containing film;
one or more coils positionable at least one of above or below the substrate support;
an alternating current power source coupled to the one or more coils to provide an alternating current through the one or more coils to generate a first magnetic field proximate the metal-containing film when the substrate is disposed on the substrate support;
an energy source to provide energy to the metal-containing film, when the substrate is present on the substrate support, sufficient to heat the metal-containing film;
a sensor to measure a temperature of the substrate at a plurality of times over a time period as the metal-containing film is heated from a first temperature to a second temperature; and
a controller configured to:
determine a rate of temperature change based on the measured temperature; and
determine a thickness of the metal-containing film based on a correlated response with the rate of temperature change of the metal-containing film as the metal-containing film is heated from the first temperature to the second temperature.

18. The system of claim 17 , wherein the energy source comprises:
a light source disposed at least one of above or below the substrate support, wherein the light source is focused into a beam having a diameter that is substantially equivalent to a diameter of the coil.

19. The system of claim 17 , wherein the energy source comprises:
a heating element disposed at least one of above or below the substrate support; and
a power source to provide a current to the heating element, wherein the controller controls the alternating current power source and the power source to provide power to only one of the coil or the heating element at a given time.

Assignees

• Ravid Abraham
• Applied Materials Inc

Inventors

• Ravid Abraham

Classifications

• G01R33/007 Primary

  Environmental aspects, e.g. temperature variations, radiation, stray fields (G01R33/025 takes precedence) · CPC title

• G01N27/9033

  Physics · mapped topic

• G01N27/72

  by investigating magnetic variables · CPC title

• G01B7/105

  for measuring thickness of coating · CPC title

• G01N27/9006

  Details, e.g. in the structure or functioning of sensors · CPC title