Recent content by sttan

Hi Gokul, thanks for your reply. I do understand that the narrowing of XRD FWHM could be due to the increase of grain size and/or strain relaxation after annealing. However, for polycrystalline films, the grain size effect could be dominant over the strain relaxation effect. In fact, I have...

I've some ZnO films grown on sapphire substrate. The ZnO film, however, is a highly-oriented polycrystalline film. The annealing was carried out at 800'C at different ambient, (N2, O2, etc.) After annealing, as expected, the crystallinity improved (narrowing FWHM of XRD). Resistivity...

Interesting.

Dear Gokul43201, Thank you for your information. I have overlooked this possible origin.

1. ZnO films grown on sapphire. 2. @ 4K, FE (3.373 eV), BE1 (3.359 eV) & BE2 (3.353 eV), XX (3.335 eV) @ 200K, FE (3.348 eV), BE1 & BE2 (quenched), XX (3.300 eV) 3. @ 4K, BE1:BE2:FE:XX = 1:0.86:0.34:0.26; FE:XX = 1:0.77 @ 200K, FE:XX = 1:0.59

I had done a temperature variation PL (4 to 200 K) on my samples. I have found out that there are three emission line in the PL spectra, namely free exciton (FE), exciton bound to neutral donors(DX) and an unknown peak (let's called it XX). As the temperature was increased from 4 K to 200 K...

Thanks to Marlon and Kurious... ST

Hi chem_tr. I;m sorry that i used the wrong word "dissolved". What i mean is to decompose the N2O. To my best knowledge, the most stable phase for N2O is N=N-O. So the bond between N and O will break first at high temperature. I'm wondering after this, if the N and N will form triple-bond...

I'm wondering if the nitrous oxide will totally dissolve at temperature of 350'C?

I'm wondering why the amorphous phase materials have wider bandgap compared to its crystalline phase. To my best knowledge, the bonding mechanism does not changed as the material transform from crystalline phase to amorphous phase. So what causes it has larger bandgap? ST