Broadband optical sources emitting low pulse energy have attracted significant attention owing to their remarkable potential for quantum technology. One of the obstacles to achieving this objective is the weak anomalous dispersion. In this study, supercontinuum generation (SCG) from 645.3 nm to 851 nm pumped by a Ti:sapphire femtosecond laser at a center wavelength of 800 nm is demonstrated by using a high-order mode (transverse electric TE20) and engineering the dispersion within the high nonlinear refractive index material, the tantalum pentoxide (Ta2O5) waveguide. The total on-chip average pulse energy of around few pJ used to excite SCG shows clear future for applications.