A radio-frequency integrated circuit chip package with at least one integrated aperture-coupled patch antenna, said package comprising: at least one planar patch formed in a first metal layer; at least one planar ground plane formed in a second metal layer spaced inwardly from said planar patch and parallel thereto, said ground plane being formed with at least one coupling aperture slot therein, said slot being opposed to said patch; at least one feed line formed in a third metal layer spaced inwardly from said ground plane and parallel thereto; at least one radio frequency chip spaced inwardly from said feed line and coupled to said feed line and said ground plane; a first substrate layer (126, 128) spaced inwardly from said feed line, said first substrate layer (126, 128) being formed with a chip-receiving cavity, said chip being located in said chip-receiving cavity; a second substrate layer (106,108,109) interposed between said ground plane and a plane defined by said patch; a third substrate layer interposed between said ground plane and said feed line; a reflector spaced inwardly from said feed line, by said first substrate layer (126, 128) and opposed to said coupling aperture slot; characterised by further comprising: an additional substrate layer located outwardly from said at least one planar patch, wherein said at least one planar patch is formed on an inner surface of said additional substrate layer; an air cavity formed in said second substrate layer (106,108,1 09) between said patch and said coupling aperture slot with said planar patch being located in said air cavity; and a vent hole (152, 352) formed in said second substrate layer (106,108,109) or said additional substrate in communication with said air cavity, so as to vent said cavity. at least one planar patch formed in a first metal layer; at least one planar ground plane formed in a second metal layer spaced inwardly from said planar patch and parallel thereto, said ground plane being formed with at least one coupling aperture slot therein, said slot being opposed to said patch; at least one feed line formed in a third metal layer spaced inwardly from said ground plane and parallel thereto; at least one radio frequency chip spaced inwardly from said feed line and coupled to said feed line and said ground plane; a first substrate layer (126, 128) spaced inwardly from said feed line, said first substrate layer (126, 128) being formed with a chip-receiving cavity, said chip being located in said chip-receiving cavity; a second substrate layer (106,108,109) interposed between said ground plane and a plane defined by said patch; a third substrate layer interposed between said ground plane and said feed line; a reflector spaced inwardly from said feed line, by said first substrate layer (126, 128) and opposed to said coupling aperture slot; characterised by further comprising: an additional substrate layer located outwardly from said at least one planar patch, wherein said at least one planar patch is formed on an inner surface of said additional substrate layer; an air cavity formed in said second substrate layer (106,108,1 09) between said patch and said coupling aperture slot with said planar patch being located in said air cavity; and a vent hole (152, 352) formed in said second substrate layer (106,108,109) or said additional substrate in communication with said air cavity, so as to vent said cavity. an additional substrate layer located outwardly from said at least one planar patch, wherein said at least one planar patch is formed on an inner surface of said additional substrate layer; an air cavity formed in said second substrate layer (106,108,1 09) between said patch and said coupling aperture slot with said planar patch being located in said air cavity; and a vent hole (152, 352) formed in said second substrate layer (106,108,109) or said additional substrate in communication with said air cavity, so as to vent said cavity.