We have fabricated a laser array module using a passive self-aligned flip-chip bonding technique. Silicon optical bench was used as a submount with PbSn (Tm=183¢J) solder bump and V-grooves. A 4-channel laser array was flip-chip mounted with coupling efficiency of 56% to cleaved 62.5/125£gm multimode fiber ribbons. The optimum fabrication parameters were bonding time of 20 seconds and bonding load of 10g. The average misalignments were measured to be 1£gm and 5£gm for X and Y directions , respectively.

In recent years, even though the light output of GaN-based LED continues to increase, the brightness (~20 lm/W) is still low compared to conventional lighting systems and it is necessary to further improve the light extraction of LEDs. In this study, we utilize flip-chip technique, photoresist microlenses, reflectors and thermoelectric cooler to increase the light extraction of GaN MQW LED. Electroluminescence (EL) and power angular distribution are used to measure the light output intensity of LED. From temperature dependent current-voltage (I-V-T) characteristics, the charge carrier transport mechanisms at different biased regions are also investigated. In the results, back emission of LED with SiO2/Al reflector has maximum light intensity ( 3.28£gW ) , which is higher than front emission one ( 2.73£gW ) in vertical emitting area ( at 90 angles). LED with P.R. microlenses (refractive index, n=1.62) on backside could improve the light extraction of LED (about 1.2 times) as well. The enhancement of light output is duo to the reduction of light absorption from the metal contact and Fresnel¡¦s transmission losses at GaN (n=2.4)/air (n=1) interface. Finally, we fabricate a high brightness LED with above light enhancement design. EL intensity of LED is increased about 1.25 times than conventional one. Therefore, we can manufacture a LEDs array with above designs to obtain high light output for future solid-state illumination.