Apparatus, method, and computer program product for deconvolution analysis
A deconvolution analysis apparatus includes a sputtering rate calibrating unit that calibrates a depth profile resulting from a depth analysis on a sample to be estimated by using a sputtering surface analysis, according to a depth change of a sputtering rate in an initial sputtering; and a deconvolution analysis unit that performs a deconvolution analysis on the depth profile whose depth axis is extended, so as to make a depth change of a depth resolution in the initial sputtering apparently constant.
1. A deconvolution analysis apparatus comprising:
a sputtering rate calibrating unit that calibrates a depth profile resulting from a depth analysis on a sample to be estimated by using a sputtering surface analysis, according to a depth change of a sputtering rate in an initial sputtering; and
a deconvolution analysis unit that performs a deconvolution analysis on the depth profile whose depth axis is extended, so as to make a depth change of a depth resolution in the initial sputtering apparently constant.
2. A deconvolution analysis apparatus comprising:
a depth profile obtaining unit that obtains a depth profile resulting from a depth analysis on a sample to be estimated by using a sputtering surface analysis;
a function parameter estimating unit that estimates parameters of a depth resolution function indicating an analytical distortion in the depth sputtering analysis on the sample;
a sputtering rate calibrating unit that calibrates the depth profile according to the depth change of the sputtering rate in the initial sputtering;
a depth axis calibrating unit that extends the depth axis of the calibrated depth profile so as to make the depth resolution change in the initial sputtering apparently constant;
an interpolating unit that forms 2 n data points in the depth profile with the depth axis extended and spaces the data points equally, where n is a natural number;
a depth resolution function creating unit that creates profile data of depth resolution functions by using the depth resolution function parameters, according to a number of data points and intervals between the data points in the interpolated depth profile;
an analysis unit that performs a deconvolution analysis according to the created depth resolution function profile data and the depth profile; and
a depth axis inversely calibrating unit that returns the depth axis with the data extended, analyzed with deconvolution, to the actual depth axis.
3. The deconvolution analysis apparatus according to claim 2 , wherein
the depth axis calibrating unit changes signal intensity according to a change in the depth axis when secondary ion mass spectrometry is used as a surface analysis method.
4. The deconvolution analysis apparatus according to claim 2 , wherein
the depth axis calibrating unit changes a differential value ΔZ reg of the depth axis in the depth profile as
ΔZ reg =ΔZ real /(1−exp(− b×Z app ))
where ΔZ reg is a differential value of depth axis, Z real is an actual depth axis (nm), Z app is an apparent depth axis calibrated assuming that the sputtering rate is constant in a depth direction (nm), and b is a coefficient (nm −1 ).
5. The deconvolution analysis apparatus according to claim 3 , wherein
the depth axis calibrating unit changes the signal intensity Y reg as
Y reg =Y real ×(1−exp(− b×Z app ))
where Y reg is a signal intensity, Y real is an actual signal intensity, Z app is an apparent depth axis calibrated assuming that the sputtering rate is constant in a depth direction (nm), and b is a coefficient (nm −1 ).
6. A computer program product having a computer readable medium including programmed instructions for deconvolution analysis, wherein the instructions, when executed by a computer, cause the computer to perform:
calibrating a depth profile resulting from a depth analysis on a sample to be estimated by using a sputtering surface analysis, according to a depth change of a sputtering rate in an initial sputtering; and
performing a deconvolution analysis on the depth profile whose depth axis is extended, so as to make a depth change of a depth resolution in the initial sputtering apparently constant.
7. A computer program product having a computer readable medium including programmed instructions for deconvolution analysis, wherein the instructions, when executed by a computer, cause the computer to perform:
obtaining a depth profile resulting from a depth analysis on a sample to be estimated by using a sputtering surface analysis;
estimating parameters of a depth resolution function indicating an analytical distortion in the depth sputtering analysis on the sample;
calibrating the depth profile according to the depth change of the sputtering rate in the initial sputtering;
extending the depth axis of the calibrated depth profile so as to make the depth resolution change in the initial sputtering apparently constant;
forming 2 n data points in the depth profile with the depth axis extended and spacing the data points equally, where n is a natural number;
creating profile data of depth resolution functions by using the depth resolution function parameters, according to a number of data points and intervals between the data points in the interpolated depth profile;
performing a deconvolution analysis according to the created depth resolution function profile data and the depth profile; and
returning the depth axis with the data extended, analyzed with deconvolution, to the actual depth axis.
8. The computer program product according to claim 7 , wherein
the extending includes changing signal intensity according to a change in the depth axis when secondary ion mass spectrometry is used as a surface analysis method.
9. The computer program product according to claim 7 , wherein
the extending includes changing a differential value ΔZ reg of the depth axis in the depth profile as
ΔZ reg =ΔZ real /(1−exp(− b×Z app ))
where ΔZ reg is a differential value of depth axis, Z real is an actual depth axis (nm), Z app is an apparent depth axis calibrated assuming that the sputtering rate is constant in a depth direction (nm), and b is a coefficient (nm −1 ).
10. The computer program product according to claim 7 , wherein
the extending includes changing the signal intensity Y reg as
Y reg =Y real ×(1−exp(− b×Z app ))
where Y reg is a signal intensity, Y real is an actual signal intensity, Z app is an apparent depth axis calibrated assuming that the sputtering rate is constant in a depth direction (nm), and b is a coefficient (nm −1 ).
11. A deconvolution analysis method comprising:
calibrating a depth profile resulting from a depth analysis on a sample to be estimated by using a sputtering surface analysis, according to a depth change of a sputtering rate in an initial sputtering; and
performing a deconvolution analysis on the depth profile whose depth axis is extended, so as to make a depth change of a depth resolution in the initial sputtering apparently constant.
12. A deconvolution analysis method comprising:
obtaining a depth profile resulting from a depth analysis on a sample to be estimated by using a sputtering surface analysis;
estimating parameters of a depth resolution function indicating an analytical distortion in the depth sputtering analysis on the sample;
calibrating the depth profile according to the depth change of the sputtering rate in the initial sputtering;
extending the depth axis of the calibrated depth profile so as to make the depth resolution change in the initial sputtering apparently constant;
forming 2 n data points in the depth profile with the depth axis extended and spacing the data points equally, where n is a natural number;
creating profile data of depth resolution functions by using the depth resolution function parameters, according to a number of data points and intervals between the data points in the interpolated depth profile;
performing a deconvolution analysis according to the created depth resolution function profile data and the depth profile; and
returning the depth axis with the data extended, analyzed with deconvolution, to the actual depth axis.