\documentclass[a4paper,11pt]{scrartcl}
\usepackage{tikz}
\usetikzlibrary{patterns}

\begin{document}
crosshatch pattern:
\begin{tikzpicture}
\draw[draw=black, fill=black!10, pattern=crosshatch, pattern color=black] (0,0) rectangle (1,1);
\end{tikzpicture}
\\

north east lines pattern:
\begin{tikzpicture}
\draw[draw=black, fill=black!10, pattern=north east lines, pattern color=black] (0,0) rectangle (1,1);
\end{tikzpicture}
\\

north west lines pattern:
\begin{tikzpicture}
\draw[draw=black, fill=black!10, pattern=north west lines, pattern color=black] (0,0) rectangle (1,1);
\end{tikzpicture}
\\

grid pattern:
\begin{tikzpicture}
\draw[draw=black, fill=black!10, pattern=grid, pattern color=black] (0,0) rectangle (1,1);
\end{tikzpicture}
\end{document}