Stacked multichip packages and methods of making multichip packages. A method includes using a boat having different depth openings corresponding to the length of column interconnections of the completed multichip package and masks to place proper length columns in the corresponding depth openings; placing an integrated circuit chip on the boat and attaching exposed upper ends of the columns to respective chip pads of the integrated circuit using a first solder reflow process and attaching a preformed package substrate integrated circuit chip stack to the integrated circuit and attached columns using a second solder reflow process.