This paper introduces two designs of balanced frequency triplers in 0.68 THz and 1.00 THz bands. The proposed triplers are based on discrete antiparallel Schottky diodes and quartz glass instead of terahertz integrated circuit. The merits of this work are attributed to the improvement of the diode model, the thinned quartz glass film and the machining accuracy of the waveguide. The improved LEC diode model considers not only the current-voltage (I/V) and capacitance-voltage (C/V) but also plasma resonance and skin effect. The quartz glass film is thinned to 15um and can be used for up to 1.2 THz. The machining accuracy of the waveguide is (±3) μm for terahertz applications with channel size 60 μm. The measurement shows a peak output power above 160 μW and 60 μW for the 0.68 THz and 1.00 THz triplers, respectively. Moreover, the efficiencies of the 0.68 THz and 1.00 THz triplers are around 1% and 0.6% correspondingly. The output frequency bandwidths are both more than 10%.