An image forming method and apparatus that improves the SN ratio of a low frequency component without causing losses to the data of a high frequency component. Means for Solving the ProblemsThe sputtering target is provided wherein 20 to 40 at % of Ga and 0. The barrier is easily and precisely formed in a space between the through-hole and the circuit elements coated with the water-resistant liquid without requiring an additional manufacturing cost. For example, chimneys can be positioned on the sidewalls of the upper, in the tongue, or both.