Abstract: A method of manufacturing a light emitting diode (LED) includes growing a light emitting region on a temporary substrate, bonding a transparent substrate of glass or quartz to the light emitting region and then removing the temporary substrate. A metal bonding agent also serving as an ohmic contact layer with LED is used to bond the transparent substrate to form a dual substrate LED element which is then heated in a wafer holding device that includes a graphite lower chamber and a graphite upper cover with a stainless steel screw. Because of the different thermal expansion coefficients between stainless and graphite, the stainless steel screw applies a pressure to the dual substrate LED element during the heating process to assist the bonding of the transparent substrate.

Abstract: A light emitting diode includes a double hetero structure containing an upper cladding layer with a graded composition. The light emitting diode comprises a GaAs substrate, a first ohmic contact to the substrate, an AlGaInP lower cladding layer formed on the GaAs substrate, an AlGaInP active layer formed on the lower cladding layer, an AlGaInP upper cladding layer formed on the active layer and a second ohmic contact. The AlGaInP upper cladding layer has a graded composition which increases the LED brightness and decreases the forward bias voltage of the light emitting diode. The graded composition can also be used in the upper semiconducting layer of a conventional p-n junction light emitting diode.

Abstract: A light-emitting diode having a transparent substrate contains a transparent GaP substrate having a first lattice constant, a first ohmic contact to the GaP substrate, a buffer layer having a graded lattice constant which gradually changes from a first lattice constant to a second lattice constant, a light generating region formed on the buffer layer and having the second lattice constant, and a second ohmic contact formed on the light generating region. In the present invention, light emitted to the substrate is not absorbed by the transparent substrate. Therefore, the brightness of the LED is increased and the V.sub.f value is not increased.