Semiconductor package and method of packaging semiconductor devices

A method of forming a device stack is presented. The method includes providing a temporary substrate having a temporary mounting surface. A first chip is temporarily mounted to the temporary mounting surface. A first bottom surface of the first chip is temporarily mounted to the temporary mounting surface and a first top surface of the first chip comprises first interconnects. A second chip is stacked on the first chip. The second chip includes second conductive contacts on the second bottom surface. The method also includes bonding the first and second chips together to form the device stack. The second conductive contacts are coupled to the first interconnects. The first bottom surface of the first chip is separated from the substrate to separate the chip stack from the substrate.