A method of manufacturing a nozzle for a droplet generator for a laser-produced plasma radiation source is disclosed. The method comprises disposing a glass capillary in a throughbore of a metal fitting, heating the metal fitting; and applying a pressure to the glass capillary such that the glass capillary conforms to the shape of, and forms a direct glass-to-metal seal with, the throughbore. Also disclosed is a nozzle for a droplet generator for a laser-produced plasma radiation source, and the radiation source itself, wherein the nozzle comprises the glass capillary for emitting fuel as droplets and the metal fitting for coupling the glass capillary to a body of the droplet generator, the glass capillary being conformed to a shape of a throughbore of the metal fitting, and wherein the glass capillary forms a direct glass-to-metal seal with the throughbore.