s an expanded see-through plan view of a part of FIG. 1, and FIG. 2B is a cross-sectional view as sectioned along a line IIB-IIB of FIG. 2A; FIG. 3A is a see-through plan view showing an earlier step of a process for manufacturing the part of the thin film transistor shown in FIGS. 2A and 2B, and FIG. 3B is a cross-sectional view as sectioned along a line IIIB-IIIB of FIG. 3A; FIG. 4A is a see-thr