A circuit board has an insulative layer including a first surface and a second surface opposite to the first surface. A plurality of electrically conductive patterns is formed on the first surface of the insulative layer. Conductive lands are formed in a die mounting region of the first surface of the insulative layer and electrically connected to one of the plurality of conductive patterns on the first surface. An extending pattern extends from the conductive lands to outside of the mounting region. A protective layer covers the first surface of the insulative layer and the electrically conductive patterns. A trench is formed in the protective layer to expose the conductive lands and the extending patterns.