AXT, INC. Patent applications |
Patent application number | Title | Published |
20110293890 | Low Etch Pit Density (EPD) Semi-Insulating III-V Wafers - Systems and methods of manufacturing wafers are disclosed using a low EPD crystal growth process and a wafer annealing process are provided resulting in III-V/GaAs wafers that provide higher device yields from the wafer. In one exemplary implementation, there is provided a method of manufacturing a group III based material with a low etch pit density (EPD). Moreover, the method includes forming polycrystalline group III based compounds, and performing vertical gradient freeze crystal growth using the polycrystalline group III based compounds. Other exemplary implementations may include controlling temperature gradient(s) during formation of the group III based crystal to provide very low etch pit density. | 12-01-2011 |
20110143091 | GERMANIUM INGOTS/WAFERS HAVING LOW MICRO-PIT DENSITY (MPD) AS WELL AS SYSTEMS AND METHODS FOR MANUFACTURING SAME - Systems and methods are disclosed for crystal growth including features of reducing micropit cavity density in grown germanium crystals. In one exemplary implementation, there is provided a method of inserting an ampoule with raw material into a furnace having a heating source, growing a crystal using a vertical growth process wherein movement of a crystallizing temperature gradient relative to the raw material/crucible is achieved to melt the raw material, and growing, at a predetermined crystal growth length, the material to achieve a monocrystalline crystal, wherein monocrystalline ingots having reduced micro-pit densities are reproducibly provided. | 06-16-2011 |
20100176336 | Systems, methods and solutions for chemical polishing of GaAs wafers - Chemical polishing solutions and methods are disclosed for the chemical polishing of GaAs wafers. An exemplary chemical polishing solution consistent with the innovations herein may comprise dichloroisocyanurate, sulfonate, acid pyrophosphate, bicarbonate and carbonate. An exemplary chemical polishing method may comprise polishing a wafer in a chemical polishing apparatus in the presence of such a chemical polishing solution. Chemical polishing solutions and methods herein make it possible, for example, to improve wafer quality, decrease costs, and/or reduce environmental pollution. | 07-15-2010 |
20100116196 | Systems, Methods and Substrates of Monocrystalline Germanium Crystal Growth - Systems, methods, and substrates directed to growth of monocrystalline germanium (Ge) crystals are disclosed. In one exemplary implementation, there is provided a method for growing a monocrystalline germanium (Ge) crystal. Moreover, the method may include loading first raw Ge material into a crucible, loading second raw Ge material into a container for supplementing the Ge melt material, sealing the crucible and the container in an ampoule, placing the ampoule with the crucible into a crystal growth furnace, as well as melting the first and second raw Ge material and controlling the crystallizing temperature gradient of the melt to reproducibly provide monocrystalline germanium ingots with improved/desired characteristics. | 05-13-2010 |
20100001288 | Low Etch Pit Density (EPD) Semi-Insulating GaAs Wafers - A method for manufacturing wafers using a low EPD crystal growth process and a wafer annealing process is provided that results in GaAs/InGaP wafers that provide higher device yields from the wafer. | 01-07-2010 |