A monolithic microwave integrated circuit fabrication techinques suitable for a wideband amplifier have been designed and developed. The designed process utilizes MESFET's fabricated on the MOCVD grown epitaxial layer with 1mm gate length, dielectric material of ECR-$Si_3N_4$ or sputtered $SiO_2$ with film thickness of 2000$\mbox{\AA}$ NiCr thin film resistor and air bridge formed by Auelectro-plating. The process has 9 mask levels. The developed process was proven to be applicable to MMIC implementation by successfully fabricating active and passive elements such as MESFET's inductors, capactiors and resistors. A GaAs wideband feedback amplifier was designed and successfully fabricated using the developed process. The amplifier has a single-stage configuration with one MESFET, three inductors, one resistor and one capacitor. The perfomance of the amplifier was measured using on-wafer probing techniques with 8510B automatic network analyzer. The amplifier has 6.5dB power gain with 0.2dB gain flatness over the 3-dB bandwidth from below 0.5GHz to 5.1GHz. The maximum input and output VSWR are 3.5 and 1.8 respectively over the operating frequency range. The amplifier chip size is 1.1x0.7mm$^2$.