Circuit board with buried circuit pattern

Abstract

A circuit board includes: an insulator having a groove; a circuit layer filling a portion of the groove; a solder pad on the circuit layer filling the remainder of the groove; and a circuit pattern electrically connected with the circuit layer, the circuit pattern buried in the insulator such that a portion of the circuit pattern is exposed at a surface of the insulator.

1 . A circuit board comprising:
 an insulator comprising a groove;   a circuit layer filling a portion of the groove;   a solder pad on the circuit layer filling the remainder of the groove; and   a circuit pattern electrically connected with the circuit layer, the circuit pattern buried in the insulator such that a portion of the circuit pattern is exposed at a surface of the insulator.   
     
     
         2 . The circuit board of  claim 1 , wherein the circuit pattern is buried in either surface of the insulator. 
     
     
         3 . The circuit board of  claim 1 , further comprising a metal film interposed between the circuit layer and the solder pad. 
     
     
         4 . The circuit board of  claim 3 , wherein the circuit layer is formed at a bottom of the groove and at a side wall of the groove in extension from the bottom,
 and the metal film covers the circuit layer.   
     
     
         5 . The circuit board of  claim 1 , wherein the solder pad contains at least one of lead (Pb), gold (Au), and silver (Ag). 
     
     
         6 . The circuit board of  claim 3 , wherein the metal film contains at least one of gold (Au) and nickel (Ni).