Methods for making semiconductor devices by low temperature direct bonding

A method for making at least one semiconductor power device with current conduction in a vertical direction from a plurality of silicon substrates, the method comprising the steps of:

• processing at least one surface of each of two silicon substrates to form at least one of a doped region;
• bonding the silicon substrates together at hydrogen terminated surfaces so that the at least one processed surface of each of the two silicon substrates define outer surfaces of the semiconductor power device;
• and
• annealing the bonded together silicon substrates at an anneal temperature less than about 800° C.

A method for making at least one semiconductor power device with current conduction in a vertical direction from a plurality of silicon substrates, the method comprising the steps of:

• processing at least one surface of each of two silicon substrates to form at least one of a metal layer and a doped region;
• cleaning surfaces to be bonded of at least one of hydrocarbons and metals;
• bonding the cleaned silicon substrates together so that the at least one processed surface of each of the two silicon substrates define outer surfaces of the semiconductor power device;
• and
• annealing the bonded together substrates at an anneal temperature of less than about 800° C.

A method for making at least one semiconductor power device with current conduction in a vertical direction from a plurality of semiconductor substrates, the method comprising the steps of:

• processing at least one surface of each of two semiconductor substrates to form a doped region and at least one of a metal layer thereon;
• bonding the substrates together so that the at least one processed surface of each of the two semiconductor substrates define outer surfaces of the semiconductor power device;
• and
• annealing the bonded together substrates at an anneal temperature less than a higher temperature of a melting temperature of the metal layer or a reaction temperature of the metal.