INSITU MONITORING OF EPITAXIAL FILM THICKNESS BY IEMI

被引：8

作者：

YU, FH

ZHOU, ZH

STOUT, P

REIF, R

机构：

[1] M/A-Com, Inc., Burlington

[2] Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cam-, bridge

[3] Digilab Divison, Cambridge., MA 02139, Bio-Rad

来源：

IEEE TRANSACTIONS ON SEMICONDUCTOR MANUFACTURING | 1992年 / 5卷 / 01期

关键词：

Epitaxial Film Thickness Monitoring - In-Situ Thickness Measurement - Infrared Emission Michelson Interferometer;

D O I：

10.1109/66.121974

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

In-situ measurement of epitaxial film thickness by infrared emission michelson interferometer (IEMI) is presented. During in-situ experiments, epi wafers were heated inside an UHV single-wafer CVD reactor or a furnace and the IR emission from the wafers was analyzed by the Michelson interferometer. In-situ thickness measurements have been made at temperatures ranging from 150 to 900-degrees-C for a lightly doped epi layer (0.5 OMEGA-cm) on top of a heavily doped substrate (0.001-0.002 OMEGA-cm). The accuracy of in-situ measurements is 2% of the actual epi layer thickness, compared with 0.3% for ex-situ measurements. The loss of accuracy is due to a low signal-to-noise ratio. There are high and low temperature limits beyond which optical properties of epi films and substrates are indistinguishable in IR, and thickness measurement by this method can not be made. This technique can be applied to real-time in-situ measurements of epi film growth and to real-time control of epi film thicknesses. The UHV single-wafer reactor is also described.

引用

页码：34 / 40

页数：7

共 31 条

[21]

Kamins T.I., Dell'Oca C.J., In-process thickness monitor for polycrystalline silicon deposition, J. Electrochem. Soc., 119, 1, (1972)

[22]

Dell'Oca C.J., Nondestructive thickness determination of polycrystalline silicon deposited on oxidized silicon, J. Electrochem. Soc., 119, 1, (1972)

[23]

Wolf S., Tauber R.N., Silicon Processing for the VLSI Era, 1

[24]

Sze M., VLSI Technology

[25]

Cox P.F., Measurement of si epitaxial thickness using a michelson interferometer, J. Electrochem. Soc., 121, 9, (1974)

[26]

Shumann P.A., Et al., Silicon optical constants in the infrared, J. Electrochem. Soc., 118, 1, (1971)

[27]

Tolansky S., An Introduction to Interferometry

[28]

Griffiths P.R., deHaseth J.A., Fourier Transform Infrared Spectrometry

[29]

Iccnogle H.W., Platt B.C., Wolfe W.L., Refractive indexes and temperature coefficients of germanium and silicon, Appl. Opt., 15, 10, (1976)

[30]

Lukes F., Czech. J. Phys. B, 10

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