The present disclosure is related to nested heating systems. The heating system uses nested thermoelectric heating assemblies, and hot temperatures can be increased by adding intermediate nested heating assemblies. Intermediate and/or inner assemblies may be removed from the outer assembly to allow for easy transport.

The present disclosure is related to nested heating systems. The heating system uses nested thermoelectric heating assemblies, and hot temperatures can be increased by adding intermediate nested heating assemblies. Intermediate and/or inner assemblies may be removed from the outer assembly to allow for easy transport.

A package structure and method for forming the same are provided. The package structure includes a cooling substrate formed on a base substrate, and the cooling substrate includes a cooling device. The package structure includes a packaged semiconductor device formed on the cooling substrate, and the packaged semiconductor device includes a first die, and the cooling device is directly below the first die.