Dual gate transistors based on rubrene/rubrene(p+p channels) and rubrene/DFH-4T(α,ω-Diperfluorohexyl-quarterthiophene)) (p+n channels) were fabricated. Traditional dual gate transistors using only one semiconductor active layer will inevitably result in bad injection in one channel. To maximize the charge injection area for both top and bottom channels, we adopted a staggered architecture with dual semiconductor layers. Gold source and electrodes are sandwiched between the bottom channel and the top channel. In the rubrene/rubrene dual layer dual gate OFETs, the average hole mobilities in the saturation regime for both bottom and top channel are around 5 cm2 V-1 s-1. The output characteristics for both channels exhibit good linearity in small Vds region, suggesting the charge injection is effective. Depending on the bias configuration, the threshold voltage of the bottom or top channel can be continuously modulated from 35.2 V to -45.6 V. In the rubrene/DFH-4T devices, the operating mode of the dual gate devices can be controlled as a p-channel, n-channel or ambipolar OFET. The AFM (Atomic force microscope) and XRD (X-ray diffraction) characterizations show that the growth of the top DFH-4T semiconductor is regulated by the bottom rubrene single crystals with distinct orientation. The dual gate transistors have the potential to be further constructed into inverters and complex logic circuits.