Abstract: A bonding-bump (1) of small dimensions comprises a gold pedestal portion (2) formed on a circuit element (10), a nickel barrier layer (3) formed on the pedestal portion (2), and a soldering portion (5) formed on the barrier layer (3). The soldering portion (5) comprises first (6) and second (8) gold layers having an intermediate tin layer (7) sandwiched therebetween. The relative masses of gold and tin in the first, second and intermediate layers (6-8) gives the soldering portion (5) a composition corresponding to the eutectic gold-tin composition. The bonding-bump (1) may be manufactured by depositing a titanium seed layer onto the circuit element (10), removing portions of the titanium layer where there are contact pads (P) on the circuit element (10), electroplating the layers and portions (2-8) constituting the bonding-bump (1), and removing the remaining portions of the seed layer. This bonding-bond technique is used to connect circuit elements in electronic devices.

Abstract: A method of manufacturing a semiconductor device comprising a buried channel field effect transistor, which method comprises the formation of a stack of layers on a substrate (1) with an active semiconductor layer (13, 14) having a non-zero aluminium (Al) content, a semiconductor cap layer (4) without aluminium (Al), a masking layer (100) provided with a gate opening (51); a first selective etching step by means of a fluorine (F) compound in the cap layer (4) down to the upper surface (22) of the active layer (13, 14) on which a stopper layer (3) of aluminum fluoride (AlF.sub.