It is possible to make your own Arduino Board ?
The answer is YES, The reference designs for the Arduino boards are available from their specific product pages. They're licensed under a Creative Commons Attribution Share-Alike license, so you are free to use and adapt them for your own needs without asking permission or paying a fee. If you're looking to make something of interest to the community, we'd encourage you to discuss your ideas on the hardware development forum so that potential users can offer suggestions. Arduino Uno Rev3 to get all the schematics about Arduino Uno.