【正文】 embossing technique is used because of its relatively easy fabrication process. We fabricated polymer waveguides by UV embossing, which also involves fabrication of mold and replica. UV curable polymers are used as materials of waveguides and silicon mold is used to form waveguide patterns. For vertical coupling between VCSEL array and waveguide array and between the waveguide array and the PD array, we have to utilize mirror face at each end of the waveguide. To achieve this process, waveguide mold equipped with 45176。 mirror face at the ends of each waveguide. The dimension of the waveguide is 50μm height and the waveguide layout pitch is 250cm. With this mold, we performed UV embossing to make embedded type waveguides.To fabricate a 12 channel silicon waveguides mold, we etched silicon substrate with KOHsaturated isopropanol solutions in two steps: First is to make a vertical coupling path for the waveguides and the other is to make 45176。 slope, a thin film of SiO2 is grown on patterned waveguide. And photoresist is patterned at the end of the each waveguide structure and the ends of the waveguides are etched with KOHsaturated isopropanol solution to form 45176。 mirror is pleted.We fabricated 12 channel embedded waveguide array by UV embossing using the prefabricated silicon mold. Waveguide fabrication process is shown in Fig. 1. UV curable polymer, which is used as cladding layer with index as at 850 slope at the end of the waveguide to enhance coupling efficiency. And then the core polymer is dropped and a flat substrate is covered and pressed onto the core material which is also UV curable polymer with refractive index of at 850 mirror face at each end of the waveguide.View Within Article3. Microlensed VCSELOne of the approaches to collimate the light from VCSEL arrays to the waveguide is the use of microlenses [9] and [10]. This method offers an increase in coupling efficiency and alignment tolerance. The volume of a polymer drop to fabricate these lenses is approximately a few tens of picoliters. We are able to control the size of the microlenses by controlling the amount of the polymer drops and by controlling the viscosity of the materials. UV curable polymer is used for inkjetting, of which the viscosity and the refractive index are 300nm wavelength. Shows one of the microlensed VCSEL array and microlensed VCSEL has a microlens formed by the inkjetting method on the aperture of VCSEL. Inkjetting of UV curable resin on the VCSEL, lens material is aligned automatically on the aperture of VCSEL. Shows a view of the system where the output power from the microlensed VCSEL arrays is measured for their divergence. The divergence angle of the laser light from the VCSEL is shown to bee narrower by using microlenses by the collimating effect pf the light from VCSEL. Because of the microlens, the higher order modes from the VCSEL are suppressed by the cavity effect [10]. The emitted output from the VCSEL cavity is reflected back by microlens layer and is focused on the VCSEL cavity. During this process, the divergence angle of the VCSEL is reduced. In this case, the divergence angle of the VCSEL decreased from 18176。 after forming microlens. We conducted simulation study about the coupling efficiency between VCSEL and the waveguide by using the ray tracing method. As the divergence angle of the VCSEL was put into the calculation, the coupling efficiency of the VCSEL with microlens was found to be dB which were better than that of VCSEL without microlens as ?μm width, 50cm length. Refractive indices of the core and the cladding are and , respectively, at 850μm.View Within Article4. Passive alignmentSolder ball array and pin array are placed on the electrical subboards to bond the OPCB and the electrical subboards with high precision. For precision alignment, solder ball array in diameter of 450μm. The size of the solder ball is 5005mm is for alignment and the other with diameter of 200mm pin array is used for lateral alignment between the main OPCB and the subboards. Because of the impedance match, the pin array of the electrical interconnection is limited. Similar to solder ball array alignment tolerance of the pin array, about 10mm on average with standard error of 10dB for the worst case of having position errors as large as 10μm in the x–z axis and in the y axis, the coupling loss between VCSELwaveguide is dB. From the previou