The present invention provides to an Au-Sn-Bi alloy film which has an excellent bondability on a metalized layer formed on an LED element or a substrate as a bonding layer made of the Au-Sn-Bi alloy and is uniform and thin. In the present invention, an Au-Sn-Bi alloy thin film which has the thickness of 5 µm or less and includes at least a eutectic structure can be formed by using an Au-Sn-Bi alloy powder paste that mixes the Au-Sn alloy powder containing 20 wt% to 25 wt% of Sn, 0.1 wt% to 5.0 wt% of Bi, and a balance of Au, and having a particle diameter of 10 µm or less with an RA flux of 15 wt% to 30 wt%, screen printing the Au-Sn-Bi alloy powder paste in a predetermined region on the Au metallized layer, and subsequently, heating, melting and then solidifying the Au-Sn-Bi alloy powder.
