Grain size will increase, with increasing substrate temperature, or post deposition annealing. Provided the annealing is done in a purely inert atmosphere, because if they are annealed in air, the film can get oxidised. With increased substrate temperature, there will be reduced grain boundaries, with increased grain size, and the conductivity can be low. The best condition would be large grain size with few grain boundaries. If the films are semiconducting in nature, you will be able to see changes in mobility also with increasing grain size.

You can find a lot of interesting information to read in the Handbook of thin film Technilogy by Maissel and Glang, on deposition conditions and characterisation of metallic thin films.

K. Sreenivas

Thank you! Dr. K. Sreenivas for your detailed response to my query. Here is my understanding from your response: Increase in temperature yields in Increase in Grain size -> Decrease in Grain Boundary -> Eventually leading to increased conductivity, mobility due to reduced Grain boundary scattering and carrier trap sites.

Dependents upon the homologous annealing temperature first primary  recrystallization takes place by nucleation and growth process ,in which  practically the deformed lattice is completely replaced by a new unstrained grains . The orientation of the new grains differs considerably   from that of crystals they consume. The growth process is incoherent and takes place by the advance of large angle grain boundaries separating new crystals from the strained matrix. 

When primary recrystalization is complete, the metal can lower its energy further by reducing its total area of grain surface. When specimen is  exposed to extensive annealing grain boundaries straighten, small grain shrinks and large grains grow. Where the surface tensions or capillary forces (bi-product of local curvature and surface specific free energy)  become main driving forces operating  not on the boundaries but also at the triple junctions to established equilibrium configuration which is 120o junctions.

At high homologous temperatures grain growth may take place by  secondary recrystallization if the special conditions are satisfies such as that normal continuous growth is impeded by inclusions. This   'abnormal'  growth proceeds  by consuming the small grains by the motion of 120o  grain boundary junctions associated with the giant  grains surrounded by large  numbers of small ones. Final state in isotropic system is a single crystal bounded by minimum surface area dictated by external constrains having no stored strain energy.  

Here the global Helmholtz surface free energy reduction criterion plays the main role if the proper subsidiary conditions are full filled. 

Nirup! Interesting question, you've posed. Here are some additional :-)

• Would the strain state (anisotropic) and dimensional limitation in one direction play a role in the annealing kinetics and final Nano structure of the film after annealing?
• Would the substrate strain state have any influence?
• What about the influence of interface coherence and strain state?
• How dependent are "Resistance, Mobility of electrons etc." on the crystallographic direction of the grains?
• Is "epitaxial" the desired Nano structural state?
• Have any NDE in situ XRD studies been conducted to evaluate such behavior in thin films?

P.S.: The "at will" edit feature on RG is awesome isn't it? :-)

@ Tarik Ömer Oğurtani: thank you! for the detailed explanation.

@ Ravi Ananth: You have raised quite a few interesting questions.

Substrate strain state would obviously have prominent effect on film growth due to lattice mismatch. But, choosing a proper substrate would mitigate this effect to certain extent. 

Resistance and mobility of carriers experience varying degree of scattering mechanism with each grain being oriented differently. I suppose this effect is very similar to having small grain size and many grain boundaries (Correct me If I am wrong ?).

Aim of the work is to deposit a polycrystalline metallic film with resistance closer to bulk value (If possible?)

Moreover, as suggested (you and others in the present thread) a thorough literature review has to be performed to check if any NDE in-situ studies have been performed.

Here is an example of Pt thin film deposited on Si (001) substrate with several "buffer layers" in between to minimize incoherence due to incompatible lattices (I think). The estimated dimensions of individual layers are: Substrate Si (001), 1um SiO2, 30nm Ti (0001) oxidized to Rutile (001) 50nm, 100nm (111) Pt.  We have used a Panalytical X'Pert type diffractometer enhanced with one of our real time 2D imaging devices known as AXIS-TAS25 (Advance XRD Imaging System). It only took minutes to mount and "stream" real time XRD video on a "foreign" machine. This is a highly effective technique combining the advantages of both the photographic film and the quantitative proportional counter to virtually "peal off individual thin film layers" in situ :-) Progressive annealing studies using such method will yield the Nano structural changes in substrate, thin film and any buffer layer. Observations with the NIST 2000 SRM (standard reference material) indicates that the sensitivity of the 2D Bragg XRD Microscopy method is sufficient to deconvolute Nano structural information from the individual layers in this case. We continue to discover new facts in the data we have already collected and stored for "on-demand" rocking curve analyses. See for yourself in the attached images and RG post for further details. I'll continue to improve and enhance the presentation. You may download the original size images for measurements and analyses :-)

If you'd like to send me a typical sample, I'll be delighted to demonstrate feasibility using the 2D real time in situ Bragg XRD Microscopy (NDE) technique :-)

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

Thank you! for sharing valuable information.