Patent ID: 6067312
Filing Date: 2000-05-23
Classification: B82Y,H01S

Abstract:
A method for producing an arrangement composed of a MCRW-DFB laser diode and an optical waveguide, which is optically coupled to the laser diode, comprising the steps of:producing on a surface of a substrate of n.sup.+ -doped InP in a first epitaxial stepa buffer layer of n-doped InP on the surface of the substrate,a first etch stop layer of quaternary material on the buffer layer,a first layer stack which is composed of at least one layer made of n-doped InP on the first etch stop layer,a laser-active layer which is composed of at least two compressively strained quantum well layers made of a quaternary material and of at least one barrier located between the quantum well layers and made of a quaternary material, on the first layer stack anda second layer stack on the laser-active layer, said second layer stack being at least composed of a first layer of p-doped InP arranged on the laser-active layer, of a second layer of p-doped quaternary material arranged on the first layer, and of a third layer of p-doped InP arranged on the second layer and having a surface facing away from the laser-active layer,an optical grating that is a relief in the surface of the second layer stack,producing in a second epitaxial stepa third layer stack on the surface of the second layer stack containing the grating, said third layer stack being composed of a fourth layer of one of p-doped InP or ternary material that covers the grating, of a second etch stop layer of p-doped quaternary material arranged on the fourth layer and of a fifth layer of p-doped InP arranged on the fourth layer,the second layer stack, the laser-active layer and the first layer stack being removed in areas down to the first etch stop layer, so that a raised region which is composed of the first layer stack, the laser-active layer and the second layer stack and has an end face at an angle to the first etch stop layer remains on the first etch stop layer, and a region of the first etch stop layer that adjoins the end face of said raised region being uncovered alongside this raised region,producing in a third epitaxial stepa fourth layer stack which is produced selectively on the exposed region of the first etch stop layer but not on the raised region, which fourth layer stack defines the waveguide and is composed of a first optical outer layer and a second optical outer layer and an optically conductive layer of quaternary material located between the first and second outer layers, whereby the optically conductive layer lies at a level of the laser-active layer with respect to the first etch stop layer and has an end face lying opposite the end face of the raised region, andproducing in a fourth epitaxial stepa fifth layer stack on the raised region and the fourth layer stack, said fifth layer stack being composed of a sixth layer of p-doped InP and of a contact layer of p-doped InGaAs arranged on the sixth layer for application of an electrical contact.