▎ 摘　　要

NOVELTY - Preparation of graphene-carbon nanotube three-dimensional composite includes preparing medicine phthalocyanine iron and growth substrate by cutting growth substrate silicon piece, ultrasonically cleaning in acetone, ethanol and deionized water, drying the silicon wafer, placing on a boat, placing phthalocyanine iron powder on the silicon wafer, placing the boat in a quartz tube reaction chamber, pushing the boat to the heating furnace most edge, opening the protective gas argon gas bottle valve, opening the gas flow meter, which is set at 60 standard cm3/minute (sccm), starting the heating furnace for heating, where the target temperature is 900 degrees C and the heating speed is 0.5 degrees C/s, and opening the valve of the hydrogen bottle, where hydrogen gas flow rate is 10 sccm and the phthalocyanine iron does not reach the sublimation temperature. USE - The method is for preparation of graphene-carbon nanotube three-dimensional composite used in ultra-fast photodetector (claimed). ADVANTAGE - The composite realizes UV-visible-near-infrared multi-band high-sensitivity ultra-fast detection, greatly improves the heat dissipation efficiency of the device and prolongs the service life of the device. DETAILED DESCRIPTION - Preparation of graphene-carbon nanotube three-dimensional composite comprises preparing medicine phthalocyanine iron and growth substrate by cutting growth substrate silicon piece, ultrasonically cleaning in acetone, ethanol and deionized water, drying the silicon wafer, placing on a boat, placing phthalocyanine iron powder on the silicon wafer, placing the boat in a quartz tube reaction chamber, pushing the boat to the heating furnace most edge, opening the protective gas argon gas bottle valve, opening the gas flow meter, which is set at 60 sccm, starting the heating furnace for heating, where the target temperature is 900 degrees C and the heating speed is 0.5 degrees C/s, opening the valve of the hydrogen bottle, where hydrogen gas flow rate is 10 sccm and the phthalocyanine iron does not reach the sublimation temperature, filling the whole quartz tube with hydrogen, moving the phthalocyanine iron to sublimation temperature area, ensuring that the hydrogen completely reaches the silicon substrate, where phthalocyanine iron starts sublimating, introducing hydrogen for 10 minutes and starting the next operation, moving the quartz tube into the growth temperature region by pushing at 1 cm/minute, where in the pushing process, phthalocyanine iron is sublimated into black green gas, the temperature in the furnace is slightly reduced, conducting rapid sublimation, cracking, under the reducing action of hydrogen and catalyst iron particles, graphene-carbon nanotube three-dimensional composite is formed on the silicon substrate, after 15 minutes, closing the hydrogen, stopping heating, gradually cooling the furnace under the protection of argon gas, naturally cooling for 3 hours to room temperature, filling protective gas argon gas to prevent the graphene-carbon nanotube three-dimensional composite from oxidizing at high temperature, taking out the graphene-carbon nanotube three-dimensional composite, cooling the heating furnace to the room temperature, closing the argon gas and gas flowmeter, opening the quartz tube air inlet end, and pulling the boat, where silicon substrate on the quartz boat becomes gray white. An INDEPENDENT CLAIM is included for application of graphene-carbon nanotube three-dimensional composite in fast photodetector.