A method of fabricating a plurality of optical proximity sensor modules, the method comprising: providing a substrate wafer having a first surface on which a plurality of light emitters are mounted and a plurality of light detectors are mounted, wherein each light emitter is disposed adjacent to a corresponding one of the light detectors, the light emitters and light detectors being mounted on the substrate wafer in an arrangement, and wherein the light emitters are operable to emit light at a first wavelength and the light detectors are operable to detect light at the first wavelength; providing a spacer wafer composed of a first polymer material that is thermally stable up to at least 260°C and that attenuates or blocks to light at the first wavelength, wherein the spacer wafer has openings in an arrangement corresponding to the arrangement of the light emitters and light detectors on the substrate wafer; providing an optics wafer, the optics wafer comprising a blocking portion (b) composed of a second polymer material that is thermally stable up to 260°C that attenuates or blocks incident light at the first wavelength, and a plurality of first and second transparent portions (t) that are transparent to light at the first wavelength, the first and second transparent portions (t) being arranged in an arrangement corresponding to the arrangement of the light emitters and light detectors on the substrate wafer, wherein each of the transparent portions (t) includes a lens member, wherein each lens member is composed of a third polymer material that is thermally stable up to at least 260°C; bonding the substrate wafer, the spacer wafer, and the optics wafer together in a wafer stack, in which the spacer wafer is arranged between the substrate wafer and the optics wafer such that the light emitters and light detectors are disposed between the substrate wafer and the optics wafer, wherein bonding the wafers together in a wafer stack comprises bonding the substrate wafer to the spacer wafer using a heat-curable epoxy; and separating the wafer stack into a plurality of modules, each of which includes one of the light emitters and one of the light detectors. providing a substrate wafer having a first surface on which a plurality of light emitters are mounted and a plurality of light detectors are mounted, wherein each light emitter is disposed adjacent to a corresponding one of the light detectors, the light emitters and light detectors being mounted on the substrate wafer in an arrangement, and wherein the light emitters are operable to emit light at a first wavelength and the light detectors are operable to detect light at the first wavelength; providing a spacer wafer composed of a first polymer material that is thermally stable up to at least 260°C and that attenuates or blocks to light at the first wavelength, wherein the spacer wafer has openings in an arrangement corresponding to the arrangement of the light emitters and light detectors on the substrate wafer; providing an optics wafer, the optics wafer comprising a blocking portion (b) composed of a second polymer material that is thermally stable up to 260°C that attenuates or blocks incident light at the first wavelength, and a plurality of first and second transparent portions (t) that are transparent to light at the first wavelength, the first and second transparent portions (t) being arranged in an arrangement corresponding to the arrangement of the light emitters and light detectors on the substrate wafer, wherein each of the transparent portions (t) includes a lens member, wherein each lens member is composed of a third polymer material that is thermally stable up to at least 260°C; bonding the substrate wafer, the spacer wafer, and the optics wafer together in a wafer stack, in which the spacer wafer is arranged between the substrate wafer and the optics wafer such that the light emitters and light detectors are disposed between the substrate wafer and the optics wafer, wherein bonding the wafers together in a wafer stack comprises bonding the substrate wafer to the spacer wafer using a heat-curable epoxy; and separating the wafer stack into a plurality of modules, each of which includes one of the light emitters and one of the light detectors.