Experimental studies have been made on junctions prepared by alloying indium into silicon wafers. The junctions made usingn‐type silicon, the resistivity of which ranges from 0.02 to 100 &OHgr;cm, have good Ohmic characteristics, whereas the junctions made usingp‐type silicon, in the range of resistivities from 0.05 to 50 &OHgr;cm, indicate rectifying characteristics like ordinaryp‐njunctions. From the measurement of thermoelectric voltages on recrystallized layers, electrical characteristics, and capacitance of the junctions, it has been concluded that the recrystallized layer containing indium atoms showedn‐type electrical conductivity. The carrier concentration in these layers is estimated to be about 1017cm−3near the junction side and about 1019cm−3near the indium dot.