Code: Select all
\documentclass{minimal}
\usepackage{tikz}
\usetikzlibrary{shapes}
\begin{document}
\begin{tikzpicture}[
nodes={draw,ultra thick},
rectangle split,
rectangle split parts=2
]
\node {
top part
\nodepart{second} bottom part
};
\end{tikzpicture}
\end{document}