Multilayer optical interconnects offer high interconnection densities and flexible routing schemes. Signals can be routed between the different layers, which can limit the number of cross-overs. In addition, the characteristics of 2D opto-electronic elements can be fully exploited. The alignment between the different optical elements is critical for the performance of the system. Efficient coupling structures are required to couple the light signals between two layers. We propose the use of laser ablated 45 degrees mirrors, which are integrated with the waveguides. Two mirror configurations are proposed: one based on total internal reflection (TIR) and a metallized 45 degrees mirror. A two layer optical structure is presented that contains multimode waveguides and micro-mirrors. The achievable alignment accuracy between the multimode waveguides and micro-mirrors in the two layers is in accordance with the results obtained from a numerical study. Experimental realizations of the mentioned structures and the first results on the loss measurements on the mirrors are presented.