多孔硅在液体中的两种电致发光光谱

p-型硅片上制作的多孔硅在含有强氧化剂的酸液中处于正向偏压时，可先后产生两种不同的电致发光光谱．一种是红光发射，所需的工作电压极小．随着通电时间增加，红光峰位发生蓝移．这种发光可能与量子尺寸效应有关．另一种是红光猝灭之后出现的白光发射，所需的工作电压很高．由于在酸液中红光猝灭之后，多孔层中形成了一连续的SiO₂薄层，因此在高电场作用下，热电子注入该薄氧化层，从而导致白光发射 关键词：

TWO KINDS OF ELECTROLUMINESCENCE FROM POROUSSILICON IN ELECTROLYTE SOLUTIONS

Two kinds of different electroluminescence from the porous silicon grown on p-type silicon wafers were observed by applying a forward bias to porous silicon in acidic aqueous system containing strong oxidizing agents (such as 1mol·L^-1HCl, 1mol·L^-1 SnCl₄, and 1mol·L^-1 H₂SO₄+0.1mol·L^-1 Na₂S₂O₈). One was the red emission with low applied voltage (V₊≈1.4V). Its red peak shifted to shorter wavelength as the operation time increases. It is most possibly related to the quantum size effect. The other was the white emission exhibited after the red one was quenched and when high voltage was applied on (V₊>30V). It is resulted from the hot electron injection under high electric field to the thin and continuos SiO₂ sub-layer formed in the porous silicon after the red emission was quenched in the electrolyte.