Cut-off filter for integrated optics
AssigneeSiemens Aktiengesellschaft
InventorReinhard Maerz
Life of this patent
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Abstract
A cut-off filter for integrated optics, which filter has a form of a relief-like surface grating on a film or strip waveguide, is formed in a portion of the strip waveguide having a reduced layer thickness and is formed with a constant corrugation depth. Preferably, the formation of the grating is done in a simple way by simultaneously etching a depression in the strip waveguide and also etching the grating structure onto the floor of the depression with the assistance of anisotropically acting etchants.
Claims14
In a cut-off filter for integrated optics in the form of a relief-like surface grating on a strip waveguide, the improvements comprising said strip waveguide having a region of reduced layer thickness and said grating being fashioned in said region and having a constant corrugation depth.
A method for manufacturing a cut-off filter in a strip waveguide, said cut-off filter being formed by a grating formed in a floor of a depression in the strip waveguide and having a constant corrugation depth, said method comprising the steps of providing a strip waveguide, providing an etchant mask having a window on an upper surface of the strip waveguide, providing a grating structure in the window, then exposing the etchant mask and grating structure to an anisotropic etching until a layer thickness of the waveguide has been reduced to form the depression having the grating.
Dependencies are inferred from the claim text.