Patent ID: 8342385
Filing Date: 2013-01-01
Classification: B23K,H01L

Abstract:
1. A transfer process for bonding a device having a solderable surface to a first substrate having a first oxidized surface comprising: (i) placing said solderable surface proximate to said first oxidized surface in a reducing chamber, where said first oxidized surface cannot be visually observed in said reducing chamber (ii) placing a second substrate having a second oxidized surface in said reducing chamber in a way so that said second oxidized surface can be visually observed through a viewing port in said reducing chamber; (iii) selecting said first substrate and said second substrate so that the reduction of said second oxidized surface correlates with the reduction of said first oxidized surface and provides an indication of the degree of reduction of said first oxidized surface; (iv) conducting said process in a reducing environment comprising a reducing agent, where the effective distribution of said reducing agent with regard to said first substrate cannot be visually observed in said reducing chamber, said reducing environment being sufficient to reduce said second oxidized surface to a reduced second oxidized surface and said first oxidized surface to a reduced first oxidized surface; (v) irradiating said second oxidized surface with radiant energy; (vi) evaluating any change in said second oxide surface during said irradiating and correlating said change with first oxidized surface reduction and second oxidized surface reduction; (vii) abutting said solderable surface against said reduced first oxidized surface when said evaluating indicates that said first oxidized surface has been substantially reduced to the point where it can be soldered; and (viii) soldering said solderable surface to said reduced first oxidized surface.