Denso Corporation

Lpe S.p.a.

Showa Denko K.k.

National Institute of Advanced Industrial Science and Technology

Central Research Institute of Electric Power Industry

Yuichiro Tokuda

Hidekazu Tsuchida

Isaho Kamata

Norihiro Hoshino

Danilo Crippa

Francesco Corea

Takeshi Okamoto

Maurilio Meschia

Tomohisa Kato

Hideyuki Uehigashi

Silvio Preti

Kazuma Eto

Hiromasa Suo

The reaction chamber () is designed for a reactor () for deposition of layers of semiconductor material on substrates; it comprises a tube () and an injector () and a holder (); the tube () is made of quartz and has a cylindrical or prismatic shape and surrounds a reaction and deposition zone; the injector () is arranged to inject precursor gases into the reaction and deposition zone; the holder () is arranged to support a substrate in the reaction and deposition zone during deposition processes; graphite susceptor elements () are located inside the tube () for heating the reaction and deposition zone and components inside the reaction and deposition zone; an inductor system () is located outside the tube () for providing energy to the susceptor elements () by electromagnetic induction; a rotating element () in the form of a cylindrical or prismatic tube is located inside the reaction and deposition zone and surrounds the injector ().

Reaction chamber comprising a rotating element for the deposition of a semiconductor material

The reaction chamber () is used for a deposition reactor of layers of semiconductor material on substrates; it comprises a tube () made of quartz and having a cylindrical shape and adapted to be positioned in use so that its axis () is vertical; the tube () has a cylindrical inner interspace () which extends along the entire length of the tube () and which is adapted to accommodate a flowing liquid; the chamber () further comprises an annular closing element () made of quartz and fixed to a first lower end of the tube () so as to close the interspace () preventing the liquid from flowing out of the interspace at the bottom; at the top, the closing element () has an annular recess () facing the interspace () so that the flowing liquid can reach the recess () at the bottom; the chamber () further comprises a set of internal conduits () internal to the interspace (), wherein said internal conduits () extend from the first lower region of the tube () till a second upper region of the tube () to facilitate circulation of the flowing liquid in the interspace ().

Reaction chamber for a deposition reactor with interspace and lower closing element and reactor

In a silicon carbide single crystal wafer, a dislocation density contained therein is 3500 dislocations/cmor less, and a difference of the dislocation density among a wafer central part, a wafer peripheral part and a wafer intermediate part is less than 50% of an average value thereof.

Silicon carbide single crystal wafer, and methods for manufacturing silicon carbide single crystal ingot and the silicon carbide single crystal wafer

A raw material gas is supplied to a space in which a silicon carbide seed crystal is placed. A silicon carbide single crystal is grown on the seed crystal by keeping a monosilane partial pressure at 4 kPa or more and heating the space to a temperature of 2400° C. to 2700° C. The temperature of the space and supply of the raw material gas are controlled such that a temperature gradient of a growth crystal surface of the silicon carbide single crystal in a radial direction is 0.1° C./mm or less, and a radius of curvature of the growth crystal surface is 4.5 m or more, thereby producing a silicon carbide single crystal ingot having a growth length of 3 mm or more and an internal stress of 10 MPa or less. The ingot is then cut into a silicon carbide single crystal wafer.

Methods for manufacturing silicon carbide single crystal ingot and silicon carbide single crystal wafer

A silicon carbide single crystal contains a heavy metal element having a specific gravity higher than a specific gravity of iron. An addition density of the heavy metal element at least in an outer peripheral portion of the silicon carbide single crystal is set to 1×10cmor more.

Silicon carbide single crystal

A method for producing a p-type 4H&#x2014;SiC single crystal includes sublimating a nitrided aluminum raw material and a SiC raw material. Further, there is a stacking of a SiC single crystal, which is co-doped with aluminum and nitrogen, on one surface of a seed crystal.

Method for producing p-type 4H-SiC single crystal

Growing community of inventors

Miyoshi, Japan

Yuichiro Tokuda