30results about How to "Improved current scaling performance" patented technology

The invention provides a strained superlattice tunnel junction ultraviolet LED (light emitting diode) epitaxial structure and a production method thereof. The epitaxial structure from top to bottom comprises: an epitaxial growth substrate, an AlN buffer layer, an n-type AlGaN layer, a multiple quantum wells, an electron blocking layer, a strained superlattice, an n-type degenerate doped AlGaN layer, and an n-type Si-doped AlGaN layer. The strained superlattice comprises a p-type AlGaN layer and an AlyGa1-yN / AlxGa1-xN. An AlGaN energy band, under effects of a polarized electric field, moves as a whole along a low energy direction. A superlattice structure contacts a heavily doped n-type AlGaN to form a p-AlGaN / SSL / n *-AlGaN tunnel junction. Electrons of a p-type AlGaN valence band, under effects of an external electric field, carried out tunneling through a tunnel effect to one side of the n-type AlGaN, and a hole is formed in the p-type AlGaN. The n-AlGaN is used as the cladding material instead of the p-type AlGaN, so that the problem of the p-type ohmic contact is avoided.

The invention relates to an avalanche commutation diode special for a 16000A / 200-400V welding machine and a preparation method thereof. The invention solves the problems that an avalanche commutation diode special for a single welding machine has small capacity and that parallel connection and flow equalization are needed during the use of the avalanche commutation diode. An N-type (100) radial single crystal silicon piece, which has specific resistance Rho n of 5-10 Ohm-cm, diameter of 70 mm and thickness of 0.17-0.19 mm, is adopted; at the temperature of 1250 DEG C, double-surface once diffusion is carried out; the surface concentration of a surface higher-concentration region of a diffusion region is 0.06-n A, a junction depth X jP is 58-62 microns, and residual minority carrier lifetime Tao p of a base region is 9-13 Mu S; cathode-anode titanium-nickel-gold undergoes ohmic contact; a cathode table surface undergoes spray sand molding, corrosion, cleaning, passivation protection andintermediate test; and a shell is arranged, the thickness of a pipe is 5-6 mm, cold pressure welding packaging is conducted under the protection of nitrogen gas, and the thickness of the pipe is 5-6mm after the packaging. The avalanche commutation diode has stronger current expansion capability, larger capacity, better quality, higher reliability and lower use cost.

The invention discloses a large-power vertical structure LED epitaxial structure. The large-power vertical structure LED epitaxial structure includes a pre-paved Al layer, an AlN buffer layer, an AlGaN buffer layer, a u-type GaN layer, a first graphene layer, an n-type GaN layer, a multi-quantum well, a p-type GaN layer, and a second graphene layer, wherein all the above layers and the multi-quantum well are grown on an Si substrate; and the first graphene layer and the second graphene layer are formed by vapor deposition. The large-power vertical structure LED epitaxial structure has better photoelectric performance and has wide application.