Contact hole standard test device, method of forming the same, method of testing contact hole, method and apparatus for measuring a thickness of a film, and method of testing a wafer
The present invention provides a standard test device used for testing a hole of a semiconductor device. The standard test device has a structure which comprises: at least a dummy film on a base surface; at least an insulating layer which has at least one opening penetrating through the insulating layer, so that a part of a top surface of the at least dummy film is shown through the at least one opening, wherein the at least dummy film has a predetermined constant thickness at least around the at least one opening. The standard test device makes it easily possible to determine or measure a thickness of a residual film on a bottom of the contact hole.
1. A method for detecting a residual material in one or more holes that are disposed in a semiconductor wafer or disposed in a layer which is disposed on or above the semiconductor wafer, the method comprising:
irradiating the one or more holes with an electron beam; and
detecting a residual material in the one or more holes using data which is representative of an amount of substrate current generated in response to irradiating the one or more holes with the electron beam.
2. The method of claim 1 wherein irradiating the one or more holes with an electron beam further includes scanning the electron beam across the one or more holes.
3. The method of claim 1 wherein irradiating the one or more holes with an electron beam includes irradiating the one or more holes with the electron beam at a constant beam angle relative to the surface of the wafer.
4. The method of claim 1 wherein irradiating the one or more holes with an electron beam includes scanning the electron beam relative to the wafer.
5. The method of claim 1 wherein irradiating the one or more holes with an electron beam includes irradiating the one or more holes with an electron beam having a constant electron beam acceleration.
6. The method of claim 1 further including measuring a substrate current at a back surface of the wafer wherein the current is generated in response to irradiating the one or more holes with the electron beam.
7. The method of claim 6 wherein detecting a residual material in the one or more holes includes using the amount of the substrate current generated in response to irradiating the one or more holes with the electron beam.
8. The method of claim 1 wherein detecting a residual material in one or more of the holes by comparing the data which is representative of the amount of current measured to a data which is representative of a reference value.
9. The method of claim 8 wherein the reference value is generated in response to the irradiating a reference region with the electron beam.
10. The method of claim 1 wherein:
the one or more holes are arranged in a first pattern and wherein the method further includes comparing (i) the data which is representative of the amount of the current generated in response to the irradiating the one or more holes with the electron beam to (ii) an amount of a reference value; and
the reference current value is generated in response to the irradiating a reference region with an electron beam, wherein the reference region includes one or more holes arranged In the same or substantially the same pattern as the first pattern.
11. The method of claim 10 wherein the reference region is a portion of a reference wafer.
12. The method of claim 1 further including displaying information which is representative of the amount of substrate current generated in response to irradiating the one or more holes with the electron beam.
13. A system for detecting a residual material in a plurality holes disposed in a layer which is disposed on or above a semiconductor wafer, or a plurality of holes on or in a semiconductor wafer, the system comprising:
means for irradiating an electron beam on the plurality of holes;
means for determining the presence of the residual material in one or more of the plurality of holes using data which is representative of an amount of substrate current generated in response to irradiating the plurality of holes with the electron beam.
14. The system of claim 13 wherein the means for irradiating an electron beam on the plurality of holes further includes means for scanning the electron beam across the plurality of holes.
15. The system of claim 13 further including means to move the semiconductor wafer relative to the electron beam while the electron beam irradiates the plurality of holes.
16. The system of claim 13 further including means for measuring a current at a back surface of the semiconductor wafer, wherein the current is generated in response to the electron beam irradiated on the plurality of holes.
17. The system of claim 16 further including means to determine a thickness of the residual material in one or more of the plurality of contact holes using the amount of current measured by the means for measuring.
18. The system of claim 16 wherein the means for determining the presence of the residual material in one or more of the plurality of holes determines the presence of the residual material in one or more of the plurality of contact holes using the amount of current measured by the means for measuring.
19. The system of claim 18 wherein the plurality of contact holes include a pattern and wherein the means for determining the presence of the residual material in one or more of the plurality of holes determines presence of the residual material using a reference value and wherein the reference value is determined using a test region having the same or a similar pattern as the pattern of the plurality of holes.
20. The system of claim 13 further including means for displaying information which is representative of the amount of substrate current generated in response to irradiating the plurality holes with the electron beam.