4 results about "Polycrystalline aluminum" patented technology

This invention discloses an aluminum nitride precision ceramic for semiconductor devices and its preparation method, relating to the field of ceramic materials technology for semiconductor devices. The invention utilizes a chemical vapor infiltration process to grow a thick hexagonal boron nitride thin film in situ on the geometrical outer surface and subsurface pore inner walls of a polycrystalline aluminum nitride ceramic substrate. This hexagonal boron nitride thin film alternates with aluminum nitride grains in the polycrystalline aluminum nitride ceramic substrate, forming a boron nitride / aluminum nitride superlattice protective layer on the surface. When high-energy arsenic or phosphorus ions bombard the surface, the hexagonal boron nitride thin film effectively absorbs and dissipates the ion bombardment kinetic energy through an interlayer slip mechanism. Furthermore, the low atomic numbers and light atomic weights of boron and nitrogen significantly reduce the physical sputtering yield of aluminum atoms, achieving comprehensive anti-sputtering protection while ensuring a high-strength bond between the protective layer and the substrate. It also maintains the intrinsic thermal conductivity and insulation properties of AlN ceramics, making it suitable for the operating conditions of high-energy ion implanters.

A method for preparing an AlN substrate includes: (A) providing a surface-polished polycrystalline aluminum nitride (AlN) substrate; (B) forming a first AlN film via reactive sputtering using magnetron sputtering with an aluminum target, nitrogen, and argon gases to fill surface lattice defect pores; (C) removing the first AlN film by thinning and polishing, leaving filled pore areas to form a planar AlN substrate; (D) sintering the planar substrate at high temperature to enhance adhesion; (E) forming a second AlN film on the sintered AlN substrate; (F) removing the second AlN film by thinning and polishing to achieve a final AlN substrate with high thermal conductivity and low surface pore sizes.

The application provides an aluminum nitride film, which comprises polycrystalline aluminum nitride; the polycrystalline aluminum nitride is doped with 6.5-7.5 at.% tantalum; the crystal face orientation of the polycrystalline aluminum nitride is (002); and the c value in the cell parameter of the polycrystalline aluminum nitride is 0.512 nm. The application further provides a preparation method of the aluminum nitride film, which specifically comprises the following steps: at normal temperature, magnetron sputtering is performed on a substrate by using an AlTa alloy target under a mixed gas atmosphere of inert gas and nitrogen, so as to obtain the aluminum nitride film. The application further provides an application of the aluminum nitride film in the field of thin film bulk acoustic resonators.

To provide a method for producing an aluminum nitride substrate having a small surface pore diameter and high thermal conductivity.SOLUTION: A method for manufacturing a polycrystalline aluminum nitride substrate includes: a step (A) of providing a polycrystalline aluminum nitride substrate whose surface is to be polished, causing a plasma formed of nitrogen and argon to act on a first layer aluminum nitride film generated by reaction on the surface of the substrate by a magnetron sputtering apparatus, and filling a gap of a hole generated due to a defect of a crystal lattice on the surface of the substrate; a step (B) of removing the first layer aluminum nitride film on the substrate by a flattening method to leave a filling portion in the hole; a step (C) of sintering the substrate, the surface of which has been flattened, at a high temperature to enhance the adhesion density between the aluminum nitride film in the gap and the substrate; a step (D) of subjecting the substrate, the sintering of which has been completed, to hole-filling sputtering of a second layer aluminum nitride film at a slow sputtering rate; and a step (C) of removing the second layer aluminum nitride film on the substrate by a flattening method to form a second layer aluminum nitride film on the substrate. (E) leaving the filling portion in the hole to complete the manufacture of the substrate.SELECTED DRAWING: Figure 1