NOVELTY - A passive anode structure of direct methanol fuel battery based on micro electro mechanical system technology comprises methanol storage electrode plate having a methanol storage cavity on its front side and a methanol outlet on its back side; a water storage electrode plate having a water storage cavity on its front side, and oblong ditches and a current collecting layer on its backside; and a hydrophobic porous silicon film arranged between the methanol storage cavity and the methanol outlet to convey the methanol and prevent reverse flow of the water.    USE - A passive anode structure of direct methanol fuel battery based on micro electro mechanical system technology.    ADVANTAGE - The structure has simple manufacturing process; good compatibility with a traditional micro process thus allowing integration of battery with other systems; and controlled area, thickness, aperture, porosity and hydrophobicity.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for manufacture of the passive anode structure comprising:    (A) applying a double-side polished n-type crystal-oriented silicon sheet having a thickness of 500-550 mu m;    (B) executing double-side hot oxidization to grow silicon oxide to a thickness of 20-50 n and applying low pressure chemical vapor deposition to deposit silicon nitride having a thickness of 200-300 nm on two sides    (C) applying a double-side photo etching process to generate a picture of the water storage cavity on the front side;    (D) removing silicon oxide using hydrofluoric acid;    (E) applying potassium hydroxide solution (30-40 mass%), and subjecting to silicon corrosion etching under an ultrasound condition at 75-85 degrees C and power of 250-350 W to penetrate through the silicon sheet;    (F) sputtering to obtain a titanium layer having a thickness of 20-40 nm, a copper layer having a thickness of 500-800 nm and gold layer having a thickness of 100-200 nm;    (G) applying the double-side polished n-type doped crystal-oriented silicon sheet having a thickness of 500-550 mu m with resistance of 0.001-0.02 ohms;    (H) applying an anode oxidization method to grow porous silicon using hydrofluoric acid and anhydrous ethanol having a volume ratio of 1-3:1 as solution;    (I) controlling current density at 30-300 mA/cm2 until the porous silicon forms perforated holes;    (J) etching using aqueous nitric acid solution (5-20 mass%) at 70-100 degrees C for 10-30 minutes;    (K) applying toluene solution of octadecyl trichlorosilane (0.0005-0.001 mol/l) to treat the porous silicon sheet at 17.9-18.1 degrees C for 20-40 minutes to form a self-assembled monomolecular film to manifest the hydrophobic property; and    (L) adhering water storage electrode plate with methanol storage electrode plate using a polydimethyl siloxane film or a rubber tape.    DESCRIPTION OF DRAWING(S) - The drawing is a schematic view of a passive anode structure of direct methanol fuel battery.