A 10Gb/s transmitter module containing an electroabsorption modulator monolithically integrated with a distributed feedback (DFB) semiconductor laser is fabricated using the identical epitaxial layer scheme.Gain-coupling mechanism is employed to improve the single mode yield of the DFB laser,while inductively coupled plasma dry etching technique is utilized to reduce the modulator capacitance.The integrated device exhibits a threshold current as low as 12mA and an extinction ratio over 15dB at -2V bias.The small signal modulation bandwidth is measured to be over 10GHz.The transmission experiment at 10Gb/s indicates a power penalty less than 1dB at a bit-error-rate of 10 -12 after transmission through 35km single mode fiber.
The growth and device fabrication of AlGaN/GaN high electron mobility transistors (HEMTs) are carried out by using metal organic vapor phase epitaxy (MOVPE) system.Specially the performances of HEMT devices with different thickness of AlGaN layer are compared.The device with thinner spacer layer exhibits better static performance.And a maximum saturation current density of 650mA/mm and a peak extrinsic transconductance of 100mS/mm are obtained from the devices with gate length of 1μm.
