Patent RU-2746849-C1 (RU)
Title: Method of manufacturing a magneto-resistive spin led (options)
Inventor: DOROKHIN MIKHAIL VLADIMIROVICH
IPC: H01L43/10
Filed: 2020-08-27
Granted: 2021-04-21
Abstract: FIELD: physics; semiconductors. 
     SUBSTANCE: present invention relates to methods for manufacturing a magneto-resistive spin LED in which the intensity of radiation and the degree of circular polarization can be independently controlled using a magnetic field. The method involves the formation of the semiconductor part of a magneto-resistive spin LED, which is a light-emitting heterostructure, by growing structures on a semiconductor single-crystal substrate of gallium arsenide with either n-type or p-type conductivity, by MOCVD (Metalorganic Chemical Vapor Deposition) at atmospheric pressure in a hydrogen stream, at a temperature of 500-650ºC. To form a semiconductor buffer layer and a semiconductor spacer layer of gallium arsenide, trimethylgallium and arsine are used at a ratio of 1.1-1.8 trimethylgallium to arsine flow. Trimethylgallium, trimethylindium, and arsine are used to form the radiating layer, which is a quantum well made from a solid solution of In x Ga 1-x As. The growth of the layers is carried out at a rate of 1-10 A/s. During the growth process, gallium arsenide layers are doped using pulsed laser sputtering of targets directly in the reactor. In this case, silicon targets are used to create n-type gallium arsenide, and zinc targets are used to create p-type gallium arsenide. The resulting light-emitting heterostructure is applied to the surface of the ferromagnetic Schottky contacts and a non-magnetic metal layer by electron-beam evaporation. To do this, in the 1 st  variant of the method, a dielectric layer of Al 2 O 3  is first grown through a mask on a semiconductor spacer layer at a temperature of 150-250ºC, then a ferromagnetic Schottky contact is formed from CoPt at a temperature of 200-400ºC, then a layer of non-magnetic metal is applied at a temperature of 50-100ºC. The growth of the layers is produced at a residual gas pressure of 5*10 -6  Torr. Contacts with a diameter of 0.05-1 mm are formed, which are closed with a photoresist, and photolithography is performed using a photomask. In the 2 nd  variant of the method, a dielectric layer of Al 2 O 3  is first grown by electron-beam evaporation at a temperature of 150-250ºC, then a ferromagnetic Schottky contact is formed from a CoPd alloy at a temperature of 150-400℃, then a layer of non-magnetic metal is applied at a temperature of 50-100ºC. After forming a dielectric layer of Al 2 O 3 , a ferromagnetic layer of CoPd, and a non-magnetic layer, a photoresist is applied, photolithography is performed using a photomask, and these layers are pitted in the area around the parts that are covered by the photoresist. Contacts with a diameter of 0.05-1 mm are formed. Next, using an accelerator, ion implantation of the area around the parts closed by the photoresist is performed with He ++  ions with energy of 10-40 keV and a dose of 10 13 -10 14  cm 2 . Then, without removing the photoresist, a dielectric layer of Al 2 O 3  is applied by electron-beam evaporation in vacuum. Growth is produced at a residual gas pressure of 5*10 -6  Torr and a temperature of 150-250ºC. After implantation and application of the dielectric, the photoresist is removed. Further, the magneto-resistive element is formed by electron-beam evaporation in a vacuum at a residual gases pressure in a chamber of 5*10 -6  Torr. In this case, a buffer layer of chromium is first applied at a temperature of 120-200ºC. To apply the ferromagnetic layers of the magneto-resistive element, the Co 90 Fe 10  alloy is sprayed from the crucible, to form a non-magnetic layer separating the two ferromagnetic layers of the magneto-resistive element, copper is sprayed from the crucible. The ferromagnetic layers and the non-magnetic layer separating them are applied at a temperature of 50-100ºC. A protective layer of GaMn is formed by pulsed laser deposition in vacuum, the composition thereof corresponds to the chemical formula Mn x Ga 5  (x=2-3). In this case, the growth is produced at a residual gas pressure of 10 -5 -10 -6  Torr and a temperature of 200-400ºC. The formed structure is split into separate magneto-resistive spin LEDs so that each of them has one formed contact. The formation of the base contact to the substrate is carried out. 
     EFFECT: increase in the information capacity of semiconductor elements, which are memory cells in the circuits for storing, transmitting and processing information. 
     23 cl, 7 dwg