A method of manufacturing a device which starts with a support bar with a first main surface provided with a groove suitable for accommodating a semiconductor element. The groove has walls on which conductor tracks are provided which continue over the first main surface. This method is particularly suitable for making support bars which serve as envelopes for semiconductor elements. The conductor tracks are provided through patterning of a conductive material by means of a patterned photoresist which is provided on the support bar and irradiated from two directions, at such an angle to the first main surface and to the groove that the bottom of the groove is not irradiated, whereas portions of the walls and of the first main surface are irradiated, after which the photoresist and an applied layer of conductive material are brought into a pattern. This method is more reliable than the known method. In the new method, the geometry of the support bar is used for irradiating the photoresist. An edge of the groove screens the bottom of the groove from irradiation. Irradiation from two directions insures that the photoresist on the first main surface and on both walls of the groove is irradiated.