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Guided-mode-selective focusing grating coupler, which couples out not TE0 mode but TE1 mode to a free space wave, was designed at around 850-nm wavelength for constructing a wavelength-division-multiplexing chip-to-chip optical interconnection board. The coupler was fabricated in a slab waveguide consisting of a Ge-SiO2 main-guiding core, a SiO2 subguiding core, a Si-N grating layer, and a high-reflection layer. Coupling efficiencies for TE0 and TE1 modes were obtained to be 5% and 46%, respectively, with 0.1-mm interaction length. The focus spot size of 3×1 μm was obtained for TE1 mode.