SIGNIFICANCE OF SUBSTRATE TEMPERATURE ON ELECTRICAL CONDUCTIVITY, HALL EFFECT, AND THICKNESS OF BILAYER HETEROJUCTION ORGANIC SOLAR CELL USING RHODOMYRTUS TOMENTOSA (AITON) HASSK AND IXORA COCCINEA L DYE. J. Teknol. 2016;78(3). doi:10.11113/jt.v78.7467