Design, Fabrication And Test Of Polymer Arrayed Waveguide Grating Device

With the rapid growth of mordern communications capacity, the single channel transmission capacity of existing optical fiber network has been nearly saturated. It has become the focus of attention that how to improve communication system performance, increase bandwidth to meet the growing demand for communications business. The effective solution to this problem is to use Dense Wavelength Division Multiplexing (DWDM) technology. This technology allows a single optical fiber transmission capacity to double on the basis of growth in high-speed TDM, It has solve the problem of inadequate transmission about a communications network. It has the broad prospects for development. Now in the commercial WDM market,there are three major categories: Thin Film Filter (TFF), Fiber Bragg Grating (FBG), Arrayed Waveguide Grating (AWG). TFF products is the preferred device to achieve the channel number is less than 16 WDM system. The limitations is difficult to achieve 0.8nm below about the channel spacing and more than 16 the number of channels. FBG is similar with TFF. But the biggest drawback about FBG is the largest insertion loss. However, AWG products has overcome these shortcomings, can be prepared is less than 100 GHz, the number of multi-channel WDM products.Smith M K in Delft University in 1988 brought forward the concepts and principles about AWG. The development directions about AWG has two major trend: one is improving the device's integration, increasing the number of channel and reducing the number of channel spacing. The other is to improve the performance of the device, improve the level of output wavelength, resolve the temperature of the device and polarization-dependent. The polymer AWG was first made in 1994. Nowadays, the performance index has reached or exceeded inorganic AWG device.The AWG is based on Roland's concave grating imaging principle, it is consist of three parts: the input/output waveguide, the planar waveguide and the array waveguide. The input/output waveguide and aray waveguide are linked by two planar waveguide. And input and output waveguide symmetrical distribution of the device at both ends and are located in the circumference of the Roland circle. Because the difference length between the neighboring waveguide maintaining a certain value. So that the specific wavelengths of light come out from a particular output channel. We complete the devide the wide spectrum signal. The other way round, we can change different signal into a wide spectrum signal. AWG devices in addition to multiplexing demultiplexing capabilities, can assemble with other device in order to achieve other functions.This paper is use computer-aided to analyse AWG with Beam Propagation method. We introduce the effective index method (EIM) and the weighted index method (WIM) in detail. We have designed 9×9 channels and 33×33 channels AWG. And we also have showed every key parameters which would be needed in the software WDM Phaser. We simulate that we put the transitional tapered waveguide in the key positions that is at the boundary between input/output waveguide and planar waveguide, at the boundary bentween planar waveguide and array waveguide or at the port about input/output channel. The transitional tapered waveguide can reduce the loss and widen the spectrum bandwidth.We choose to the copolymer consisted of PMMA GMA and the high refractive index regulator to make AWG device. And SU-8 2005 UV-sensitive material make another device. We introduce the parametric technology preparation. The SU-8 2005 UV-sensitive materials compared with PMMA & GMA polymer decreases plasma etching and aluminum deposition process. It makes the device yields greatly improved. For example, we measure the transmission loss of the device that made up of SU-8 2005. We test the performance of the devices which are made up in two different materials under the wide spectrum light source. The device realize the demultiplexer.