Dear Udaya,

I would like to introduce some conceptual answer which may help to find the proper technique,

Basically, there are two methods to from vertical nanowirs, the growth method and the etching method also the subtraction method.

The subtraction method is very controllable since the geometry of the wires are determined by lithography and etching. The copper nanowirs can be directly formed by this method. While for silver you need to deposit continuous layer and then produce nanowires by lithography and etching.

The growth method requires some deposition apparatus with substrate heating facility.

Then you have firstly to nucleate the vertical growth by some sort of alloying, eg for silicon one uses very gold islands. once a crytallite is formed as the nucleation site it grows spontaneously on the vertical direction. I do not know nucleate the growth over copper. but it must be a material which alloys with copper at relatively low temperature.

There may existing another antinuclear methods rather than low temperature alloying such as using LASER to pit the surface.

Wish you success 

Vertically aligned branched silver nanowires (Ag BNWs) were synthesized by electrodeposition method. Tou could follow this article (DOI: 0.1109/NANO.2014.6968005)

@Abdelhalim Zekr: Thank you very much sir. I am trying using electrodeposition technique. I am still learning. As far as the technique of lithography is concerned, we dont have the facility. It is very difficult for me.

Is there any simple template based method which we can use? Like using Anodic alumina membranes (AAO)?

@Sujoy Sarkar: Thank you very much sir. Do you have any idea about porous alumina membranes?

Dear Udaya,

What do need is found in the paper titled:Direct growth of copper nanowires on a substrate for boiling applications. Please follow the Link:http://www.rit.edu/~w-taleme/Papers/Journal%20Papers/J101.pdf.

IN this process the metal wires are deposited through porous alumina sheets stacked to the substrate by electro-chemical  deposition methods. This method may be called deposition through pores or tiny holes.

wish you ssuccess

@Abdelhalim Zekry: Thank you very much sir. I have already read this paper. I want to do similar works. The main challenge is the availability of these membranes. There is no provider for this kind of membranes. If you have any contact kindly help me.

Dear Uday,

you can find the AAO membranes in the following links

http://www.sigmaaldrich.com/catalog/product/aldrich/z694916?lang=en®ion=IL

or

http://www.2spi.com/category/spi-pore-silver-membrane-filters/

otherwise you can prepare in your lab also

Please follow the article

http://www.2spi.com/category/spi-pore-silver-membrane-filters/

@Sujoy Sarkar: thank you very much sir. Please guide me if you have more details.

Dear Uday,

The AAO membrane is available in Bangalore based company. Please check the details given below

BIOLIX Technologies LLP.

No: 12 3rd Floor, JR Arcade, 1st Block, 80ft Road, Koramangala, Bangalore 560034.

Tel:+91-80-40974773. Fax:+91 80 25504596, Mbl:+91-9900846627,9880211966, 9986951830.

Email : [email protected]

@Sujoy Sarkar : Thanks a lot for your help sir.

Hi there,

We provide researchers with low-cost electrodeposited metallic nanowires, having different lengths and diameters. Contact: [email protected]