177results about How to "Improve output power density" patented technology

This invention relates to an improved coating method for preparing oxide ceramic membrane. The method comprises: (1) preparing a support; (2) preparing a slurry of the raw materials; (3) coating the slurry onto the support; (4) spin-coating and leveling; (5) drying the membrane blank; (6) repeating the steps 3-5; (7) calcining at a high temperature. The method is convenient and rapid, and has such advantages as high raw materials utility and good membrane quality. The zirconium oxide electrolyte membrane thus prepared can be used to prepare solid oxide cells with high output power density and stable performance.

The invention provides a double-heterojunction gallium nitride based HEMT (High Electron Mobility Transistor) taking aluminum-gallium-nitrogen as a high-resistance layer, comprising a substrate, a nucleating layer, an unintentionally-doped high-resistance layer, an unintentionally-doped high migration rate layer, an aluminum nitride inserting layer, an unintentionally-doped barrier layer and an unintentionally-doped gallium nitride or aluminum-gallium-nitrogen cap layer, wherein the nucleating layer is manufactured above the substrate and is 0.01-0.50 microns in thickness; the unintentionally-doped high-resistance layer is manufactured above the nucleating layer; the unintentionally-doped high migration rate layer is manufactured above the unintentionally-doped barrier layer; the aluminum nitride inserting layer is manufactured above the unintentionally-doped high migration rate layer and is 0.7-5 nm in thickness; the unintentionally-doped barrier layer is manufactured above the aluminum nitride inserting layer; and the unintentionally-doped gallium nitride or aluminum-gallium-nitrogen cap layer is manufactured above the unintentionally-doped barrier layer and is 1-5 nm in thickness. According to the double-heterojunction gallium nitride, the channel electron migration rate and the limiting capability to two-dimensional electronic gas are obviously improved; power leakage of the buffering layer is inhibited; and meanwhile, crystal lattice stress of the barrier layer is reduced, the defect density is reduced, and the stability and the reliability of the work of a device are improved.