41results about How to "Decrease the density of surface states" patented technology

The invention relates to the technical field of production of wide bandgap semiconductor materials and devices and discloses a method for improving the performance of a GaN-based field-effect transistor, the method comprises: mixed pre-treatment solution is adopted to carry out the surface pre-treatment of the surface of a device before the passivation of the GaN-based field-effect transistor during the production process of the GaN-based field-effect transistor, then a compound dielectric layer of silicon nitride and oxygen-rich silicon nitride is deposited on the surface of the device afterthe surface pre-treatment, and the GaN-based field-effect transistor is passivated. The use of the method can solve a surface original oxide layer which is existed on the surface of AlGaN for a long time, eliminate the AlGaN surface state which is induced by the surface oxide layer, solve the surface state existing in an AlGaN and silicon nitride interface, the current collapse effect which is induced by the surface original oxide layer and the significant increase of the reverse gate leakage current caused by the conventional passivation and improve the stability and the reliability of GaN-based HEMT.

The invention discloses a method of manufacturing GaN-based field-effect transistors, which includes steps of surface-finishing a GaN-based material layer, depositing a silicon oxide protective layer,forming lithographic alignment marks via lithography, dry-etching the silicon oxide protective layer, evaporating marked metal, forming source-drain patterns via lithography, dry-etching the siliconoxide protective layer, evaporating source-drain metal, annealing alloy at high temperature, forming shielding active region patterns via lithography, forming active region isolation via ion implantation, then wet-etching the silicon oxide protective layer, depositing silicon nitride on the surface of the GaN-based material, passivating field effect transistors, forming grids via electron-beam direct writing or optical lithography, dry-etching the silicon nitride and the GaN-based material layer at the top to form a gate-recessed structure, evaporating gate metal and metal wiring. The method of manufacturing GaN-based field-effect transistors avoids the surface of the GaN-based material being exposed in air, prevents the surface of the GaN-based material from being polluted during fabrication process, and inhibits current collapse effect of AlGaN / GaN HEMTs.

The invention discloses a planar indium gallium arsenic light-sensitive chip with surface passivation improved and a manufacturing method. According to the structure of the planar indium gallium arsenic light-sensitive chip, an N-type InP layer, an indium gallium arsenic intrinsic absorption layer, an N-type InP cap layer, a SiNx passivation layer, a P-electrode and a thickened electrode (8) are grown on a semi-insulating InP substrate in sequence. The manufacturing process is improved on the basis of an original process, and comprises removal and vulcanization of a diffusion mask and silicon nitride passive film growing through an inductive coupling plasma chemical vapor deposition (ICPCVD) technology. The planar indium gallium arsenic light-sensitive chip with surface passivation improved and the manufacturing method have the advantages the passivation layer of the chip is even in structure; the surface state density of a device is effectively reduced, and the surface can be prevented from being oxidized again through a vulcanization film formed on the surface; damage of the process to the surface of materials is small, the film is compact and is in stress fit with the substrate, the element bonding state is good, and the passivaition effect is excellent.