GB/T 29505-2013Test method for measuring surface roughness on planar surfaces of silicon wafer (English PDF)

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009.

This standard is under the jurisdiction of the National Technical Committee on Semiconductor Equipment and Materials of Standardization Administration of China (SAC/TC 203) and its subcommittee on materials.

Drafting organizations: GRINM Semiconductor Materials Co., Ltd., China Nonferrous Metals Industry Institute of Standards, Metrology and Quality.

1 Scope

This standard describes the measurement principles, apparatus and procedures of three methods commonly used to measure the surface roughness of silicon wafers - profilometers, interferometers and scatterometers - and specifies standard scan patterns for measuring the roughness of a local area or of the whole wafer surface, together with the definitions of the areas and their abbreviations.

This standard applies to roughness measurement on planar silicon wafer surfaces. It can also be used for other types of planar wafer material, but not for roughness measurement in the edge region of the wafer.

This standard does not apply to measuring instruments with a spatial wavelength bandwidth of 10 nm or less.

2 Normative references

The following documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

GB/T 14264, Semiconductor materials - Terms and definitions

3 Terms and definitions

For the purposes of this document, the terms and definitions given in GB/T 14264 and the following apply.

3.1 autocorrelation function: the Fourier transform of the power spectral density function. It expresses the self-similarity between the surface profile and the same profile shifted laterally.

3.2 autocorrelation length: the lateral shift required for the autocorrelation function to fall to 1/e of its value at zero shift. Values of 10% or 0 are sometimes used instead of 1/e.

3.3 bi-directional reflectance distribution function; BRDF: a description of how light scattered from a surface is distributed in direction, defined as the scattered radiance normalized by the incident irradiance; it is approximated by the scattered power per unit projected solid angle divided by the incident power.

3.4 Nyquist criterion: the shortest detectable spatial wavelength, equal to twice the sampling interval.

3.5 one-dimensional grating equation: in its most common form, the expression giving the positions of the diffraction orders produced by a one-dimensional sinusoidal grating.

3.6 power spectral density (PSD) function: a function describing surface features, given by the squared magnitude of the Fourier transform coefficients of the surface profile per unit spatial frequency.