Method for independent control of volatile dopants in liquid phase epitaxy

A method for the independent control of the concentration of each of a plurality of volatile dopants in a doped layer of a semiconductor material fabricated by liquid phase epitaxy upon a semiconductor substrate, comprising the steps of:

• a. providing a substantially vapor-tight volume;
• b. providing a first quantity of at least one element of the semiconductor material within said volume;
• c. heating said first quantity to a selected temperature sufficient to melt said first quantity;
• d. saturating the molten first quantity with a desired quantity of a first volatile dopant;
• e. immersing said substrate in said molten first quantity;
• f. providing a source of a second volatile dopant at a position below and spatially removed from said molten first quantity;
• g. independently heating said source of said second volatile dopant to cause a vapor thereof to rise without use of a carrier gas and be present at a selected partial pressure above a surface of said molten first quantity to achieve a desired concentration of said second volatile dopant within said molten first quantity at the selected temperature thereof;
• and
• h. cooling said molten first quantity containing said substrate and said first and second volatile dopants in their respective concentrations, to fabricate a doped layer of said semiconductor material upon said substrate.