Dear Tombak, 

as i know, you can not obtain xrd pics of your thin film ( < 200 nm) with classical XRD aparatus i.e high diffraction angle of the beam, but there is an other way, that consist of make enough time to scan Theta angle ( 2 hours analysis for 1 sample)

All my best

Dear Dr Tombak

Are you measuring in the Bragg Brentano geometry, I assume, Therefore it could be difficult to get signal if samples are very thin. In the D8 you could try to do grazing incidence by setting the incidence angle below 5 degree, lets say, 1, 2 and 5 degree and also increasing the step time (depending on your detector). Only be sure that the beam does not impact directly on the detector, you would fry it... D8 has kind of a screen in the front of the incidence beam to avoid this... Try this configuration and tell me if it works. Send me data if you consider it valuable.

Regards. F Caballero-Briones

You need a göbel mirror as primary optics and a theta-two theta diffractometer (bruker D8 advance), with that accesory you can use incident angle (theta) around 1 o 2 degrees, if you film is very thin you can use 0.5 degrees. Also you could check sample holder configuration. 

First of all, are the films polycrystalline or amorphous .. ie during growth or after was any annealing done to promote growth.If not, then u might get an amorphous film and that's why u don't see any peaks on Si or quartz.

Also are u looking at the data with Y axis on log scale, because the signal from thin, and possibly amorphous or polycrystalline films is usually weak. 

Also if the films are really amorphous and thin enough(80 nm or so), can u try to do X-ray reflectivity (XRR) to check that there is any film there, if film-substrate and film-air interface are smooth enough then u should get some oscillations..

Also  film don't have to be 200 nm thick as mentioned by earlier. 

Hope this helps

D8 configuration is like this:

-Bragg-Brentano geometry

-With göbel mirror as primary optics.

-Theta: 0 degree

-Two theta 0 degree

-Power:1600 W

-Initial Count (theta=0 and two theta=0): 8,000,000

-Initial Count (theta=0 and two theta=3): 14,000,000

I can still not measure

Dear Wadekar

How can I get  X-ray reflectivity (XRR) to check that there is any film there by the D8 software

Well we faced the similar problem with Advance D8. The best way to obtain the diffraction pattern of thin films in my opinion is to run a XRD measurement of sample holder with and without the sample. Then subtract the diffraction patterns using the software provided by Bruker (Eva).Hope it helps.

Regards,

Maziyar

The XRD analysis depends on several parameters

such as incidence angle , Xray wavelength for ex CuKalpha 1.54 ang, 2theta range,

the surface state, if your sample has a surface formed with two or more materials , you should choose the suitable material to analyse

See the following discussion using Bruker D8 HRXRD for XRR measurements of the NIST2000SRM. As you found, we found the substrate reflection easily but the epi reflection which is slightly off orientation with the substrate is still elusive. We will find it next Tue/Wed at MIT XRD lab by optimizing the reflection for the epi. I'll post once I have the unequivocal XRD rocking curve data for the thin epitaxial films grown by MBE.

Ahmet! What is the expected morphology of your thin film, as Paritosh queried? I must assume polycrystalline, because you are still using the B-B optics (focusing?).

1. Use XRR to determine film thickness & roughness. Also substrate roughness. See XRR data for NIST2000SRM below.

2. Compute extinction depth (penetration depth) for each constituent on the sample surface.

3. Use GIXRD (grazing incidence angle) to maximize the signal contribution of the thin film on the RCP (rocking curve profile).

https://www.researchgate.net/post/What_is_the_best_way_to_interpret_REAL_TIME_3D_X_Y_Omega_2Theta_reciprocal_space_relative_intensity_data_from_HRXRD_rocking_curve_analyses

My films have almost smooth surface, sputter depositted and AFM rougness value is a few nanometers and they have not thinner than 200 nm. I expect polycrystalline in nature, Rigaku XRD says they are polycrystalline. I use BB geometry.

Next step I will try XRR measurements.

Can u tell what is ur film? I can calculate the omega angle for u to do the GIXRD as mentioned  by our friends.

Have you already tried grazing incidence? Enter the XR wizard and made a adhoc routine.  You need to made the measurements setting up the detector pivoting and the tube at a fixed angle, below 5deg and never 0 deg (you are not illuminiating the surface)

In a perfect world  Your may use a Goebel mirror with a grazing incidence attachment. Otherwise You may go with a fixed omega angle of 1 ° using a scintillation counter with a small divergence slit (detector scan), but since your conditions are off-focus (Bragg-Brentano) and your FWHM become large.

Thank you all for your valuable contribution