摘要:
The present invention relates to a process for producing magnetic metal particles for magnetic recording, comprising:heat-treating goethite particles having an aluminum content of 4 to 50 atom % in terms of Al based on whole Fe to obtain hematite particles; andheat-reducing the hematite particles at a temperature of 200 to 600° C.,the goethite particles being obtained by adding a peroxodisulfate to a reaction solution comprising:a ferrous salt aqueous solution anda mixed alkali aqueous solution comprising:an alkali hydrogen carbonate aqueous solution or alkali carbonate aqueous solution andan alkali hydroxide aqueous solution before initiation of an oxidation reaction of the reaction solution, and then conducting the oxidation reaction.
摘要:
A semiconductor device includes a die pad having a surface on which a first solder bonding layer is formed, and made of metal; and a semiconductor element fixed on the first solder bonding layer on the die pad by a solder material made mostly of bismuth. The first solder bonding layer is made of a softer material than the solder material, a recess is formed in a part of the first solder bonding layer by pressing the solder material against the first solder bonding layer, and the solder material partially fills the recess.