“…Since uneven substrates which CNTs are grown on can reduce electric-field-screening effect, the combination of rugged substrates and CNTs improves the emission performance of CNTs effectively. Recently, in order to mitigate the electric-field-screening effect, several research groups have designed patterned and aligned CNTs [15], CNT growth on copper nanowire [16], silicon (Si) nanowire [17] and Si nanoporous pillar arrays [18].…”