- SEMI MF1619 - Test Method for Measurement of Interstitial Oxygen Content of Silicon Wafers by Infrared Absorption Spectroscopy with p-Polarized Radiation Incident at the Brewster Angle
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 F1619; previously published September 2012.
Control of the oxygen content is essential for silicon wafers to be used for advanced devices and integrated circuits. It is desirable to be able to measure the oxygen content of product wafers, nondestructively and without regard for back surface finish. This Test Method provides a means for reducing the influence of the back surface condition on the measurement.
This Test Method may be used for routine process monitoring, quality control, materials acceptance, and research and development.
This Test Method covers determination of the absorption coefficient due to the interstitial oxygen content of commercial monocrystalline silicon wafers by means of Fourier transform infrared (FT-IR) spectroscopy. In this Test Method, the incident radiation is p-polarized and incident on the test specimen at the Brewster angle in order to minimize multiple reflections.
Since the interstitial oxygen concentration is proportional to the absorption coefficient of the 1107 cm- 1 absorption band, the interstitial oxygen content of the wafer can be derived directly using an independently determined calibration factor.
The test specimen is a single-side polished silicon wafer of the type specified in SEMI M1. The front surface of the wafer is mirror polished and the back surface may be as-cut, lapped, or etched with rms roughness less than 0.9 µm.
This Test Method is applicable to silicon wafers with resistivity greater than 5 Ω·cm at room temperature.
Referenced SEMI Standards
SEMI M1 — Specification for Polished Single Crystal Silicon Wafers
SEMI M59 — Terminology for Silicon Technology
SEMI MF1188 — Test Method for Interstitial Atomic Oxygen Content of Silicon by Infrared Absorption with Short Baseline