<jats:title>Abstract</jats:title>
<jats:p>A well-ordered molecular arrangement is a necessary condition for “band transport” in molecular semiconductor materials, and thus it is important for donor–acceptor molecular junctions for applications in advanced organic optoelectronic devices. In this study, the heteroepitaxial growth of an acceptor material C<jats:sub>60</jats:sub> on a single-crystal (001) surface of dinaphtho[2,3-<jats:italic>b</jats:italic>:2′,3′-<jats:italic>f</jats:italic>]thieno[3,2-<jats:italic>b</jats:italic>]thiophene (DNTT), a representative high-mobility donor material, is demonstrated. Surface X-ray diffraction analysis indicated spontaneous alignment of the nearest-neighbor molecular direction of the C<jats:sub>60</jats:sub> crystallites uniquely to the <jats:bold>
<jats:italic>a</jats:italic>
</jats:bold>-axis of the DNTT.</jats:p>