Multi-layer circuit board

A multi-layer circuit board formed by laminating at least seven circuit boards, each circuit board comprising a substrate having its surface, a plurality of lands or vias and circuit patterns formed on said surface of the substrate, each of said circuit patterns having one end connected to said land or via and the other end extending outwardly from a land area where said plurality of lands or vias are arranged under such a condition that at least one circuit pattern can pass through a first space between two adjacent lands or vias and at least four circuit patterns can pass through a second space between lands or vias at both ends by removing an intermediate one from consecutively arranged three lands or vias;

• said multi-layer circuit board comprising:
• first to third circuit boards comprising a first circuit board having a plurality of said lands or vias arranged equidistantly in column and row directions to form an area array corresponding to an arrangement of electrodes of an electronic part which is to be mounted on said circuit board so that said electrodes are electrically connected to said respective lands or vias;
• said first circuit board comprising said circuit patterns which are connected to all the lands or vias positioned on a first, outermost row of the area array of the first circuit board, and are connected to alternatively selected lands or vias positioned on second and third rows of the first circuit board;
• a second circuit board having a plurality of said lands or vias arranged so as to correspond to said lands or vias of the first circuit board to which no circuit patterns on the first circuit board are connected;
• said second circuit board comprising said circuit patterns which are connected to all the lands or vias positioned on the second row of the second circuit board, corresponding to said lands or vias of the first circuit board, to which no circuit patterns on the first circuit board are connected, and are connected to all the lands or vias positioned on forth and fifth rows of the second circuit board;
• a third circuit board having a plurality of said lands or vias arranged so as to correspond to said lands or vias of the second circuit board to which no circuit patterns on the second circuit board are connected;
• said third circuit board comprising said circuit patterns which are connected to all the lands or vias positioned on the third row of the third circuit board, corresponding to said lands or vias of the second circuit board, to which no circuit patterns on the second circuit board are connected, and are connected to all the lands or vias positioned on sixth and seventh rows of the third circuit board;
• fourth to sixth circuit boards also comprising respective circuit patterns which are arranged in the same manner as the circuit patterns on said first to third circuit boards with the circuit patterns of the fourth circuit board connected to all the lands or vias positioned on the third circuit board;
• the fourth circuit board having a plurality of said lands or vias arranged equidistantly in column and row directions to form an area array corresponding to an arrangement of electrodes of a second electronic part which is to be mounted on said fourth circuit board so that said electrodes are electrically connected to said respective lands or vias;
• said fourth circuit board comprising said circuit patterns which are connected to all the lands or vias positioned on a first, outermost row of the area array of the fourth circuit board, and are connected to alternatively selected lands or vias positioned on second and third rows of the fourth circuit board;
• the fifth circuit board having a plurality of said lands or vias arranged so as to correspond to said lands or vias of the fourth circuit board to which no circuit patterns on the fourth circuit board are connected;
• said fifth circuit board comprising said circuit patterns which are connected to all the lands or vias positioned on the second row of the fifth circuit board, corresponding to said lands or vias of the fourth circuit board, to which no circuit patterns on the fourth circuit board are connected, and are connected to all the lands or vias positioned on forth and fifth rows of the fifth circuit board;
• the sixth circuit board having a plurality of said lands or vias arranged so as to correspond to said lands or vias of the fifth circuit board to which no circuit patterns on the fifth circuit board are connected;
• said sixth circuit board comprising said circuit patterns which are connected to all the lands or vias positioned on the third row of the sixth circuit board, corresponding to said lands or vias of the fifth circuit board, to which no circuit patterns on the fifth circuit board are connected, and are connected to all the lands or vias positioned on sixth and seventh rows of the sixth circuit board;
• and
• a seventh circuit board having a plurality of said lands or vias arranged so as to correspond to said lands or vias of the sixth circuit board to which no circuit patterns on the sixth circuit board are connected;
• said seventh circuit board comprising said circuit patterns which are connected to all the lands or vias positioned on eighth and ninth rows of the sixth circuit board.