大气环境下STM金针尖场蒸发纳米书写实验研究

Nano\|lithography by Field Evaporation of Au Tip in The Configuration of STM in Atmosphere

用金作ＳＴＭ针尖，通过一个窄脉冲电压（～４Ｖ，～３００ｎｓ），可在原子平坦的Ａｕ表面稳定观察到原子堆的形成。用这种方法我们成功地进行了纳米书写。实验表明原子堆的形成存在一个很陡的阈值电场，而且正负电压脉冲皆可形成原子堆，我们初步认为它是一个场离子蒸发过程。

Atom mounds were formed by appling 4V,300ns voltage pulses on Au tip in scanning tunneling microscope (STM) in atomsphere.Each mound measures about 30 nm in diameter and 1\|2 nm in height.With the aid of this,we succeed in writing nanometer scale characters.There exists a narrow threshold field and we refer it a field evaporation process.Both positive and negative ions could be field evaporated.The re\|examination of charge\|exchange model for the field evaporation in STM and experiments on other metals will be published elsewhere.