Abstract: An electrical soldering device in the form of a soldering gun has a transformer disposed in a housing with a primary winding and a secondary winding. The transformer is supplied from an A.C. source, such as a voltage mains. The soldering tip is in the form of a resistance wire bent into a loop and connected to the secondary winding of said transformer. The secondary winding of the transformer is formed of a cylindrical sleeve of metallic material, preferably copper, surrounding the coil of the primary winding. The cylindrical sleeve has a continuous slit formed therein extending approximately parallel to its cylinder axis. The slit defines mutually opposite edge regions to which the resistance wire is connected. A frequency converter connected in the current supply line to the transformer increases the frequency, preferably into the kilohertz range.

Abstract: Layers containing silicon and oxygen are formed by means of low pressure chemical vapor deposition. As a source for silicon and oxygen, tetraethylorthosilicate (TEOS) is used which is drawn into the low pressure area of the deposition apparatus in liquid form and evaporated there. If necessary, oxygen is introduced into the low pressure area. The reactants are directed into the reaction zone which has been heated to a predetermined temperature, and reacted there. The reaction product is deposited onto the substrates provided therein. If the deposited layer is to comprise still further elements, liquid substances containing such elements are mixed with the liquid TEOS prior to being drawn into the evaporating area, in a ratio adapted to the desired layer composition. Both with respect to layer thickness and composition the layers deposited are highly homogeneous.