I saw online someone talking about capacitance of a straight wire, I was surprised because capacitance is result of facing two plates very near to each other, electrons and holes attract each other and they gather at the surface of two nearly held plates...
So a question came up in my mind that if "capacitance of a straight wire" is true then dose resistor has capacitance also because resistor is also a wire of semiconductor?
so I want to study at this level.
I hope what i said make sense to you.
It did not make much sense to me, at least. If you are not trying to pull our collective legs here, I'll try to make an example.
You state that you have studied electronice for 6 months, but you did not tell at what level. Based on your questions so far, I'll assume that it is relative early in your education in electronics. Electronics, like any subject you want to learn, need to mature as you progress in your study. You need to start with the basic properties of the basic components, and gradually increase your knowledge from that base. The practical use of the components will eventually help you to expand the theoretical knowledge into a more or less useful practical experience. This is where you may start doing your own designs, based on proper knowledge. During this time you will experience that much of the existing designs and application notes from different manufacturers of electronic components, can be reused and/or used as 'platforms' for your own designs.
You don't need to invent the wheel every time you start a design.
Regarding the study of materials used in components, I would assume that you'll need a degree in physics, as a start. Then start in a research laboratory, at a company or facility researeching for new materials, if you get the security clearance.