NOVELTY - Fabrication of a photo-sensing device package (10) comprises forming on a passivation layer (120), a sealing structure for filling a gap to establish a closed loop configuration contiguously enclosing a photo-sensing area in sealed manner, where an internal cavity is defined between a photo-sensing die and substrate (100).    USE - The method is for fabrication of a photo-sensing device package useful for all types of photo sensors or photo detectors, such as charged coupled device or complementary metal oxide semiconductor, camcorders, digital still cameras, PC cameras, mobile phone cameras, personal digital assistant and handheld cameras, security cameras, toys, automotive equipment, and biometrics; and linear array image sensors such as those used in fax machines, scanners, bar code readers and scanners, and digital copiers. It is useful in packaging non-imaging photo-sensors such as single diode or four-quadrant diodes used in motion detectors, light level sensors, and positional or tracking systems.    ADVANTAGE - Volume and positional accuracy are controlled during application of the sealing layer material to ensure that enough sealing material is applied to form an impermeable closed loop sealing layer, while preventing too much of such material from being applied, so as to mitigate if not altogether eliminate the likelihood of any excess material flooding into and contaminating the photo-sensing area.    DETAILED DESCRIPTION - Fabrication of a photo-sensing device package comprises:    (A) establishing a substrate formed of a material transparent to light within a predetermined range of wavelengths, the substrate having a front surface (105);    (B) forming on the substrate front surface a set(s) of patterned metal and passivation layers defining bonding pads (115, 225);    (C) establishing a photo-sensing die(s) having a photo-sensing area(s) defined on its front side;    (D) forming on the photosensing die front side, bonding pads disposed peripherally outside the photo-sensing area;    (E) flipchip mounting the photo-sensing die and substrate one onto the other to form interconnection joints disposed about the photo-sensing area, where the front side of the photo-sensing die is spaced by a gap from the front surface of the substrate; and    (F) forming on the passivation layer formed in the second step, a sealing structure for filling the gap to establish a closed loop configuration contiguously enclosing the photo-sensing area in sealed manner, where an internal cavity is defined between the photo-sensing die and substrate.    DESCRIPTION OF DRAWING(S) - The figure is a schematic cross-sectional view of the photo-sensing electronic package formed with a dam structure included in a sealing structure.    Photo-sensing device package (10)    Substrate (100)    Front surface (105)    Bonding pads (115, 225)    Passivation layer (120)    Sealing layer (140)