The invention relates to a soft support 
bridge type silicon micro-piezoelectric 
microphone chip which comprises a 
silicon substrate with a square conical hole which is small at the top and big at thebottom, a square compound vibration membrane which consists of a first 
silicon nitride membrane layer, a 
silicon dioxide membrane layer and a second 
silicon nitride membrane layer is covered on the front surface of the silicon substrate, and a third 
silicon nitride membrane layer and a fourth 
silicon nitride membrane layer are sequentially covered on the back surface of the silicon substrate; thethird and the fourth 
silicon nitride membrane layers both have central square holes; one pair of opposite sides of the vibration membrane respectively etch a vertical narrow slot penetrating the vibration membrane, and the 
vertical projection of each narrow slot is positioned on the inner side of the edge of the square hole in the front surface of the silicon substrate; a lower 
electrode, a 
piezoelectric membrane and an upper 
electrode are sequentially deposited on the vibration membrane; a 
polyimide membrane is deposited on various parts on the front surface of the silicon substrate; the compound vibration membrane which is etched with the vertical narrow slots and the 
polyimide membrane commonly constitute a soft support anti-sound leakage 
bridge type vibration membrane; two sides of thevibration membrane are fixedly supported, and strain can be produced during the vibration process; in order to prevent the 
microphone from producing sound leakage through the narrow slots, the soft 
polyimide membrane is deposited on the narrow slots, thereby being capable of effectively preventing sound leakage phenomenon.