Method and apparatus for manufacturing copper and/or copper alloy ingot having no shrinkage cavity and having smooth surface without wrinkles

A method for manufacturing a high purity copper or copper alloy ingot, comprising the steps of:

• providing copper or copper alloy in a cavity of a crucible;
• heating the crucible with the copper or the copper alloy contained in the crucible cavity to form a molten state of the copper or the copper alloy in an inert gas environment, a reducing environment or a vacuum;
• injecting inert gas into the molten copper or molten copper alloy;
• providing a mold having a bottom, a lid disposed at a top of the mold and a sidewall connected together to form a mold cavity therein;
• transferring the inert-gas-injected molten copper or inert-gas-injected molten copper alloy into the mold cavity having an inert gas atmosphere with the sidewall surrounded by a furnace;
• and
• conductively cooling the bottom of the mold while simultaneously heating the sidewall of the mold in a manner to form a temperature gradient in the sidewall increasing from the bottom towards the top of the mold.