Abstract: A method for the manufacture of A.sub.3 B.sub.5 light-emitting diodes, particularly of light-emitting (Ga,Al)As diodes with Te and Zn as doping materials is provided. A first n-doped GaAlAs layer is epitaxially applied on a GaAs substrate from an n-doped (S,Se,Te) Ga,Al,As melt and after an interim precipitation without contact with the GaAs substrate, preferably on an auxiliary substrate, a GaAlAs layer p-doped with Zn or Mg is deposited on the substrate already epitaxially coated with the n-GaAlAs layer. Efficient light-emitting diodes are obtained.

Abstract: A luminescent diode is comprised of n- and p-conductive layer components in which a graded bandgap is present and between which a pn-junction is present. The p-conductive layer component is produced by means of an additional zinc additive during an epitaxy processing utilized for manufacturing the device. The luminescent diode of the invention has improved efficiency and a higher modulation capability cutoff frequency.

Abstract: The invention relates to a method and apparatus for manufacturing epitaxial Ga.sub.1-x Al.sub.x As:Si films via liquid-phase epitaxy, using a boat in a quartz tube. The Ga, which is contained in a graphite boat, open at the long side, is baked out first. The Ga-melt is allowed to run onto GaAs substrate wafers, on which Si is deposited, and to be drawn into the gap between the GaAs-substrate wafers and the plane graphite surfaces. The thin Ga-melt formed above the GaAs substrate wafers is then brought into contact with the melted Al and is allowed to cool.According to the method of the invention, luminescence diodes of the (Ga, Al) As type, the emission of which is in the wave range of 650 to 800 nm, can be constructed.

Abstract: Apparatus for manufacturing epitaxial Ga.sub.1-x Al.sub.x As:Si films via liquid-phase epitaxy, using a boat in a quartz tube. The Ga, which is contained in a graphite boat, open at the long side, is baked out first. The Ga-melt is allowed to run onto GaAs substrate wafers, on which Si is deposited, and to be drawn into the gap between the GaAs-substrate wafers and the plane graphite surfaces. The thin Ga-melt formed above the GaAs substrate wafers is then brought into contact with the melted Al and is allowed to cool.

Abstract: An improved monitoring device for monitoring a crystal pulling process taking place in a high pressure drawing chamber in which the mounting for a high pressure window at the same time encloses the end of a quartz rod whose other end projects freely into the drawing chamber ending in the vicinity of the melt with the mount inserted into the device in a pressure tight manner using a nipple threaded into the drawing chamber, the monitoring device permitting good observation of the process without precipitation of the volatile element of the semiconductor compound on the high pressure window.