Methods for forming conductive elements for microelectronic components, related conductive elements, and microelectronic components, assemblies and electronic systems incorporating such conductive elements

A process, comprising:

• exposing a seed material on bond pads on a substrate surface;
• electroplating columns of solder material onto the exposed seed material;
• electroplating tubes of a metal material unreactive with the solder material on the bond pads around and to a height of the columns of solder material;
• and
• electroplating heads of solder material onto the columns of solder material and upper ends of the tubes of the metal material unreactive with the solder material to form metal pillar structures.

A microelectronic component assembly, comprising:

• a first microelectronic component;
• a second microelectronic component at least partially superimposed over the first microelectronic component;
• and
• conductive pillars extending between the first microelectronic component and the second microelectronic component, the conductive pillars comprising metal tubes on bond pads of the first microelectronic component and a solder material within each metal tube protruding from the metal tube and bonded to a terminal of the second microelectronic component.

A method of joining conductive structures of microelectronic components, comprising:

• placing a first microelectronic component over a second microelectronic component;
• aligning a metal pillar protruding from a bond pad of the first microelectronic component with a terminal of the second microelectronic component;
• heating the first and second microelectronic components to a temperature above a melting point of solder material substantially filling and protruding from the metal pillar to melt the solder material to wick to the terminal and pull molten solder material from within the metal pillar to leave a void within the metal pillar between the solder material and the bond pad;
• and
• reducing a temperature of the first and second microelectronic components below the melting point of the solder material to solidify the solder material to bond to an interior surface of the metal pillar and to the terminal.

An electronic system comprising:

• one or more input devices;
• one or more output devices;
• one or more microprocessor devices;
• and
• one or more memory devices,
• at least one of the input devices, output devices, microprocessor device and memory devices configured as microelectronic components,
• wherein at least one microelectronic component comprises electrical connections to another microelectronic component or to a substrate, the electrical connections configured as tubular metal pillars extending from bond pads and having solder material bonded to interiors thereof, extending therefrom and bonded to the another microelectronic component or the substrate, the tubular metal pillars having an interior void between the solder materials and the bond pads.