Ecologically Friendly Metal-Silicide Semiconductor Reserch. Applications of Laser Processing to Ecologically Friendly Semiconductor.

Abstract

As ecologically friendly semiconductors became a target of intense investigations, the interest in pulsed laserdeposition (PLD), which is the most popular laser-based deposition technique today, has been renewed as apowerful tool to produce iron silicides, a typical ecologically friendly semiconductor material. PLD is characterizedby the non-equilibrium production of atoms from the laser target, which helps the crystallization of the disilicides. As a result, crystallized disilicides were produced even at room temperature by using a FeSi2 target. Anotheradvantage of PLD is its simplicity, which was fully utilized by using an iron target. In this case, single β-phasedisilicides were produced on the silicon substrate heated to 600°C to 700°C. In addition, PLD has beenproven to be an effective tool to fabricate photodetectors. The photosensitivity of the iron silicide/Siheterostructures produced by PLD increased dramatically when they were fabricated at 800°C. The sensitivitypeak was observed around 1040 nm with the illumination from the iron silicide. The sensitivity reached to0.27 A/W when the silicon side of the heterostructure was illuminated. The feasibility to fabricate solar cellsby PLD was discussed.