Apparatus and method for determining depth profile characteristics of a dopant material in a semiconductor device

A method for determining a depth profile of a dopant material in a region of a semiconductor device, comprising:

• illuminating the region with light at each of two or more illumination wavelengths to produce scattered light;
• determining, for each one of the two or more illumination wavelengths, an intensity characteristic of the scattered light for at least one spectral line, at a different wavelength than the one of the two or more illumination wavelengths, which is attributable to the dopant material;
• obtaining, for each illumination wavelength, an absorption coefficient of light from a test semiconductor device which is similar to the semiconductor device;
• and
• determining the depth profile of the dopant material using each intensity characteristic, absorption coefficient, and illumination wavelength.

A method for determining a depth profile of a dopant material in a region of a semiconductor device comprising:

• illuminating the region with light at each of two or more illumination wavelengths to produce scattered light;
• determining, for each one of the two or more illumination wavelengths, an intensity characteristic of the scattered light for at least one spectral line, at a different wavelength than the one of the two or more illumination wavelengths, which is attributable to the dopant material, wherein the relationship between each intensity characteristic and the corresponding wavelength is defined by:
• ##EQU3## where I is a particular one of the intensity characteristics, .lambda. is the particular illumination wavelength corresponding to the particular intensity characteristic, .lambda.' is a wavelength of the spectral line which is attributable to the dopant material, A(.lambda.,.lambda.'), B(.lambda.), and B(.lambda.') are profile constants dependent upon the particular illumination and spectral line wavelengths, T is the thickness of the region of the semiconductor device, k(.lambda.) is the absorption coefficient of the region of the particular illumination wavelength, k(.lambda.') is the absorption coefficient of the spectral line wavelength, z is the depth of the region, and C(z) is the depth profile;
• obtaining, for each illumination wavelength, an absorption coefficient of light from a test semiconductor device which is similar to the semiconductor device;
• and
• determining the depth profile of the dopant material using each intensity characteristic, absorption coefficient, and illumination wavelength.

A method for determining a depth profile of a dopant material in a region of a semiconductor device, the method comprising:

• illuminating the region with light at two or more illumination wavelengths;
• obtaining for each one of the two or more illumination wavelengths at least a portion of at least one associated Raman spectrum;
• integrating the intensity of each Raman spectrum over at least a portion of one or more spectral lines and determining, for each Raman spectrum, an intensity characteristic of the one or more spectral lines, at a wavelength different than the one of the two or more illumination wavelengths, attributable to the dopant material;
• and
• using each intensity characteristic and the respective illumination wavelength to determine the depth profile of the dopant material in the region.

A method for in-line determination of at least one depth profile characteristic for a plurality of semiconductor devices, comprising:

• doping a target region of each of the semiconductor devices with a dopant material using a set of dopant parameters;
• choosing at least one test semiconductor device from the semiconductor devices;
• illuminating the target region of the test semiconductor device with light at at least two illumination wavelengths to produce scattered light;
• integrating the intensity of the scattered light over at least a portion of one or more spectral lines and determining, for each one of the at least two illumination wavelengths, an intensity characteristic of the scattered light for the one or more spectral lines, at a wavelength different than the one of the at least two illumination wavelengths, attributable to the dopant material;
• and
• determining the at least one depth profile characteristic of the dopant material using the intensity characteristic and the at least two illumination wavelengths.

An apparatus for the production of semiconductor devices, the apparatus comprising:

• a doping apparatus for doping a region of the semiconductor devices with a dopant material;
• and
• an in-line apparatus comprising
• a light source capable of producing light at two or more illumination wavelengths,
• a detector to measure an intensity of light scattered from a semiconductor device which is illuminated by the light source, the detector measuring, at each one of the two or more illumination wavelengths, the intensity of light for one or more spectral lines having a wavelength different than the one of the two or more illumination wavelengths, and
• a processor configured to integrate the intensity of the scattered light over at least a portion of each of the one or more spectral lines to determine the depth profile.

An apparatus for determining the depth profile of a dopant material in a semiconductor device, the apparatus comprising:

• a light source capable of producing light at two or more illumination wavelengths;
• a detector to measure an intensity of light scattered from a semiconductor device which is illuminated by the light source, the detector measuring, at each one of the two or more illumination wavelengths, the intensity of light for one or more spectral lines having a wavelength different than the one of the two or more illumination wavelengths;
• and
• a processor configured to integrate the intensity of the scattered light over at least a portion of each of the one or more spectral lines to determine the depth profile from the measured intensities.