- SEMI MF1392 - Test Method for Determining Net Carrier Density Profiles in Silicon Wafers by Capacitance-Voltage Measurements with a Mercury Probe
This Standard was technically approved by the Silicon Wafer Global Technical Committee. This edition was approved for publication by the global Audits and Reviews Subcommittee on February 1, 2018. Available at www.semiviews.org and www.semi.org in July 2018; originally published by ASTM International as ASTM F1392-92; previously published May 2012.
Net carrier density is a critical parameter in growth of epitaxial layers of silicon. This Test Method provides a means for determining net carrier density without formation of a special diode structure on the layer. It may also be used in characterizing net carrier density in polished silicon wafers.
This Test Method can be used for research and development, process control, and materials specification, evaluation, and acceptance purposes.
In the absence of interlaboratory test data to establish its reproducibility (see ¶ 14.2), this Test Method should be used for materials specification and acceptance only after the parties to the test have established reproducibility and correlation.
This Test Method covers the measurement of net carrier density and net carrier density profiles in epitaxial and polished bulk silicon wafers in the range from about 4 × 1013 to about 8 × 1016 carriers/cm-3 (resistivity range from about 0.1 to about 100 Ω·cm in n-type wafers and from about 0.24 to about 330 Ω·cm in p-type wafers).
This Test Method requires the formation of a Schottky barrier diode with a mercury probe contact to an epitaxial or polished wafer surface. Chemical treatment of the silicon surface may be required to produce a reliable Schottky barrier diode. The surface treatment chemistries are different for n- and p-type wafers. This Test Method is sometimes considered destructive due to the possibility of contamination from the Schottky contact formed on the wafer surface; however, repetitive measurements may be made on the same test specimen.
This Test Method may be applied to epitaxial layers on the same or opposite conductivity type substrate. This Test Method includes descriptions of fixtures for measuring substrates with or without an insulating backseal layer.
Referenced SEMI Standards
SEMI C28 — Specification and Guide for Hydrofluoric Acid
SEMI C29 — Specification and Guide for 4.9% Hydrofluoric Acid (10:1 v/v)
SEMI C30 — Specification for Hydrogen Peroxide
SEMI E89 — Guide for Measurement System Analysis (MSA)
SEMI M59 — Terminology for Silicon Technology
SEMI MF26 — Test Method for Determining the Orientation of a Semiconductive Single Crystal
SEMI MF42 — Test Method for Conductivity Type of Extrinsic Semiconducting Materials
SEMI MF81 — Test Method for Measuring Radial Resistivity Variation on Silicon Wafers
SEMI MF84 — Test Method for Measuring Resistivity of Silicon Wafers with an In-Line Four-Point Probe
SEMI MF672 — Test Method for Measuring Resistivity Profiles Perpendicular to the Surface of a Silicon Wafer Using a Spreading Resistance Probe
SEMI MF723 — Practice for Conversion Between Resistivity and Dopant or Carrier Density for Boron-Doped, Phosphorus-Doped, and Arsenic-Doped Silicon
SEMI MF1153 — Test Method for Characterization of Metal-Oxide-Silicon (MOS) Structures by Capacitance-Voltage Measurements