The realization of integrated-optic broadband wavelength devision multiplexer for separation of 1.31µm and 1.55µm wavelength window is demonstrated based on the well known arrayed waveguide structure. Broadband characteristic with passband greater than 100nm is achieved by using low diffraction order (m = 1, 2). The number of arrayed waveguides is W = 13 and W= 7 respectively. Structure parameters especially those for the star coupler region are derived by use of the transfer-matrix formalism for layered media and the wide-angle finite difference beam propagation method. Prototypes of these structures where realised as doped silica on silicon substrate by using standard plasma enhanced chemical vapor deposition (PECVD) and reactive ion etching (RIE) techniques. The waveguide structure is based on a 7x7µm waveguide core with refractive index difference Dn = 0.005 with reference to a 20µm buffer and cladding layer. Phosphor and Boron were used as dopands of each silica layer to achieve proper adjustment of phys ical layer properties, i.e. refractive index and transformation temperature. Codopand Boron is used to open a selective thermal postprocessing of deposited layers to overcome inhomogeneous PECVD cladding layer deposition on the RIE structured waveguide