[Ifeffit] S K-edge of CdS(ZnOOH) Thin Films

[Kevin McPeak]

Hi all,

On Aug 22nd I will acquiring S K-edge XANES spectra (at APS 9-BM) of
CdS(ZnOOH) thin films that I have grown in my lab. The films are grown
in such a way that their composition and thickness vary as a function
of position. View the following pdfs for details on thickness and
composition:

http://dunx1.irt.drexel.edu/~kmm333/cdzns/figure1.pdf
http://dunx1.irt.drexel.edu/~kmm333/cdzns/figure3.pdf

The idea is to take scans at various position along the middle of the
substrate and observe how the different amounts of oxygen affect the
Sulfur species present. Foreseeable issues are:

1). The CdS(ZnOOH) films are deposited on FTO (250 nm F:SnO2 film
deposited on 2 mm of soda lime glass). There is 0.2 wt% SO3 (0.05 at%
S) in the glass according to the manufacturer. We will run a scan on
the bare FTO before starting work on CdS(ZnOOH), hopefully the SO3 in
the glass is below the detection level.

2). If the SO3 in the glass is an issue I also have a sample where the
CdS(ZnOOH) film is deposited on <100> Silicon. In earlier work I tried
using this sample at the Cd and Zn K-edge at the APS 10-BM (to reduce
scatter from the glass) but I ended up getting Bragg peaks in the
spectra. Outside of spinning the substrate (not really an option here)
do you have any suggestions for avoiding the Si Bragg peaks? I read
one paper where they discussed deglitching but I am not sure how well
that would go over with reviewers. Furthermore, grazing-incidence is
not an option at 9-BM.

All of the measurements above either have been (Cd and Zn) or will be
(S) acquired in fluorescence.

I am meeting with the beamline scientist to discuss this next Thursday
but I figured it was a good idea to get input from the list as well.

Any advice is most appreciated.

Regards,
Kevin McPeak
kmm333 at drexel.edu
312.371.5477
--
PhD Candidate
Chemical Engineering
Drexel University