Hi,
I need to design a MOSFET amplifier having a voltage gain of 10, bandwidth 250MHz,and input singnal strength 20mV peak-peak using N-MOSFET. Which is the best recommended MOSFET that can give me these characteristics? Also I would really appreciate help as to steps in which I go about designing the circuit.
Thank you very much.

 

Your external components will set the gain and there are thousands of choices for the MOSFET itself. Drill down through "Discrete Semiconductors" at http://www.mouser.com until you've leveled the playing field down to a few hundred then choose an inexpensive one that they have in stock. Usually, but not always, if they show a huge "in stock" or "on order" number it's a popular device.