A method of making a flowcell includes bonding a first surface of an organic solid support to a surface of a first inorganic solid support via a first bonding layer, wherein the organic solid support includes a plurality of elongated cutouts. The method further includes bonding a surface of a second inorganic solid support to a second surface of the organic solid support via a second bonding layer, so as to form the flowcell. The formed flowcell includes a plurality of channels defined by the surface of the first inorganic solid support, the surface of the second inorganic solid support, and walls of the elongated cutouts.