Light-Induced Passivation of Si by Iodine Ethanol Solution

AbstractWe report on our observations of light-activated passivation (LIP) of Si surfaces by iodine-ethanol (I-E) solution. Based on our experimental results, the mechanism of passivation appears to be related to dissociation of iodine by the photo-carriers injected from the Si wafer into the I-E solution. The ionized iodine (I−) then participates in the formation of a Si-ethoxylate bond that passivates the Si surface. Experiments with a large number of wafers of different material parameters indicate that under normal laboratory conditions, LIP can be observed only in some samples–samples that have moderate minority-carrier lifetime. We explain this observation and also show that wafer cleaning plays an extremely important role in passivation.

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Contactless Evaluation Of The Stress In X-Ray Mask Wafers (SiN/Si) Using A Laser/Microwave Method.

MRS Proceedings ◽

10.1557/proc-306-91 ◽

1993 ◽

Vol 306 ◽

Cited By ~ 1

Author(s):

Masatoshi Oda ◽

Akira Usami ◽

Takahisa Nakai ◽

Akira Ito ◽

Masaya Ichimura ◽

...

Keyword(s):

Carrier Lifetime ◽

Minority Carrier ◽

Minority Carrier Lifetime ◽

Microwave Method ◽

Carrier Injection ◽

X Ray ◽

Semiconductor Laser Diode ◽

Membrane Fabrication ◽

Microwave System ◽

Si Wafer

AbstractHighly accurate X-ray masks are strongly required to establish SR lithography technology. X-ray masks must be produced as accurately as the LSI devices, because a one-toone projection aligner system is used. To minimize the in-plane mask distortion, it is desirable to estimate the value of the stress and the non-uniformity in the membrane fabrication (SiN) process. The values of the stress were estimated from the measurement of the warpage and the calculation. It is very difficult to obtain the stress distribution in the SiN/Si wafer. Thus, we measured the minority carrier lifetime distribution using the non-contact laser/microwave method. The carrier injection was done by a 774nm or 904nm semiconductor laser diode, and their beam was focused to about 500 μmφ. The surface lifetime, τ s, of the SiN/Si wafer with the stress over ˜ 108dyn/cm2 decreased to 60–70% of that of the bare Si wafer. Thus, the contactless laser/microwave system can be adaptable for the characterization in the X-ray mask process.

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Minority carrier lifetime limitations in Si wafer solar cells with gallium phosphide window layers

2016 IEEE 43rd Photovoltaic Specialists Conference (PVSC) ◽

10.1109/pvsc.2016.7749953 ◽

2016 ◽

Author(s):

Stefan Janz ◽

Markus Feifel ◽

Jens Ohlmann ◽

Jan Benick ◽

Charlotte Weiss ◽

...

Keyword(s):

Solar Cells ◽

Gallium Phosphide ◽

Carrier Lifetime ◽

Minority Carrier ◽

Minority Carrier Lifetime ◽

Si Wafer

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Gate oxide integrity and minority‐carrier lifetime correlated with Si wafer polish damage

Applied Physics Letters ◽

10.1063/1.98885 ◽

1987 ◽

Vol 51 (1) ◽

pp. 54-56 ◽

Cited By ~ 3

Author(s):

J. Lee ◽

C.‐C. D. Wong ◽

C. Y. Tung ◽

W. Lee Smith ◽

S. Hahn ◽

...

Keyword(s):

Carrier Lifetime ◽

Minority Carrier ◽

Minority Carrier Lifetime ◽

Gate Oxide ◽

Si Wafer ◽

Gate Oxide Integrity

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Using minority carrier lifetime measurement to determine saw damage characteristics on Si wafer surfaces

2015 IEEE 42nd Photovoltaic Specialist Conference (PVSC) ◽

10.1109/pvsc.2015.7355744 ◽

2015 ◽

Cited By ~ 1

Author(s):

Bhushan Sopori ◽

Srinivas Devayajanam ◽

Prakash Basnyat

Keyword(s):

Carrier Lifetime ◽

Minority Carrier ◽

Minority Carrier Lifetime ◽

Lifetime Measurement ◽

Damage Characteristics ◽

Wafer Surfaces ◽

Si Wafer

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A Comparison of Surface Passivation Techniques for Measurement of Minority Carrier Lifetime in Thin Si Wafers: Toward a Stable and Uniform Passivation

MRS Proceedings ◽

10.1557/opl.2014.591 ◽

2014 ◽

Vol 1670 ◽

Cited By ~ 3

Author(s):

Bhushan Sopori ◽

Srinivas Devayajanam ◽

Prakash Basnyat ◽

Vishal Mehta ◽

Helio Moutinho ◽

...

Keyword(s):

Carrier Lifetime ◽

Surface Passivation ◽

Minority Carrier ◽

Minority Carrier Lifetime ◽

High Quality ◽

Cleaning Procedure ◽

Wafer Cleaning ◽

Spatial Uniformity ◽

Very High

ABSTRACTWe describe appropriate wafer cleaning procedure and surface passivation characteristics of various passivants used for making measurement of minority carrier lifetime (τB ) of very high quality Si wafers. These passivants include: iodine ethanol (I-E), quinhydrone methanol (QH-M), SiO2, and Al2O3. The issues related to the passivation stability and the spatial uniformity for mapping τB are also discussed.

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