Method of manufacturing wafer-level chip-size package and molding apparatus used in the method

Abstract

Provided are a method of manufacturing wafer-level chip-size packages and a molding apparatus suitable for practicing the method whereby a semiconductor wafer having a plurality of semiconductor chips formed thereon may be encapsulated. The semiconductor wafer, typically with a plurality of conductive bumps extending from the semiconductor chips, will be placed in a cavity formed between upper and lower molds. Injection molding of an encapsulant composition or compression molding of encapsulant sheets may then be used to apply encapsulating layers to the upper and lower surfaces of the semiconductor wafer in a substantially simultaneous manner, thereby reducing the likelihood of warping and mechanical damage to the semiconductor wafer. The wafer-level chip-size packages can then be separated from the encapsulated semiconductor wafer.

1 .- 12 . (canceled) 
   
   
       13 . A molding apparatus for manufacturing a wafer-level chip-size package, the molding apparatus comprising:
 a lower mold;   an upper mold;   means for selectively moving the lower mold relative to the upper mold between an open position and a closed position, the lower mold and the upper mold cooperating to form a mold cavity when in the closed position;   means for positioning a semiconductor wafer within the mold cavity;   an encapsulant injection unit arranged and configured to inject an encapsulant composition into the mold cavity; and   means for heating the encapsulant within the cavity to a temperature sufficient to initiate curing of the encapsulant.   
   
   
       14 . A molding apparatus for manufacturing a wafer-level chip-size package according to  claim 13 , further comprising:
 a lower mold support arranged and configured to support the lower mold;   a mold moving control unit arranged and configured for moving the lower mold and the lower mold support;   an upper mold support arranged and configured to support the upper mold; and   a temperature control unit arranged and configured to control the temperature of the lower mold.   
   
   
       15 . A molding apparatus for manufacturing a wafer-level chip-size package according to  claim 14 , wherein:
 the mold moving control unit includes a hydraulic actuator arranged and configured for moving the lower mold support and the lower mold toward the upper mold.   
   
   
       16 . A molding apparatus for manufacturing a wafer-level chip-size package according to  claim 13 , wherein:
 the encapsulant injection unit includes;
 an encapsulant injection controller arranged and configured to control an injection rate and an injection volume of the encapsulant composition injected into the mold cavity. 
   
   
   
       17 . A molding apparatus for manufacturing a wafer-level chip-size package according to  claim 16 , wherein:
 the encapsulant injection unit includes;
 an air tube connected to the encapsulant injection controller; 
 an encapsulant source connected to the air tube; and 
 an injection needle connected to the encapsulant source through which the encapsulant composition is injected into the mold cavity. 
   
   
   
       18 . A molding apparatus for manufacturing a wafer-level chip-size package according to  claim 14 , wherein:
 the temperature control unit includes;
 a heat controller that controls a temperature of the lower mold; and 
 a heat pipe that connects the heat controller to the lower mold. 
   
   
   
       19 . A molding apparatus for manufacturing a wafer-level chip-size package according to  claim 13 , further comprising:
 a releasing film supply arranged and configured for extending a releasing film across a mold surface; and   a vacuum arranged and configured to increase the contact between the releasing film and the mold surface.   
   
   
       20 . A molding apparatus for manufacturing a wafer-level chip-size package according to  claim 19 , wherein:
 the releasing film supply is arranged and configured to provide a first releasing film on an upper surface of the lower mold and a second releasing film on a lower surface of the upper mold; and   vacuum ports arranged on the upper surface of the lower mold and the lower surface of the upper mold whereby a partial vacuum may be applied to backside surfaces of the releasing films to secure the releasing films to the upper and lower surfaces.