Silicon field emitter array by fast anodization method

Abstract

A new fast fabrication method entailing, two step anodization of silicon with different HF solutions was used to form a high aspect ratio silicon Field Emitter Array on n-type silicon (resistivity of 0.01Ωcm). A Silicon oxide mask was used to define the field emitter array. The silicon substrate was pre-anodized with low current density for 1 minute in the dark and then anodized in HF:H2O:Ethanol solution. Finally, the porous silicon was removed by isotropic solution etching. The turn-on voltage of the fabricated field emitters was approximately 27V/μm when the emission current density reaches 1μA/cm2. This compares with the turn-on field of about 35V/μm on silicon tip array fabricated by using an isotropic etching solution of HNO3. We obtained field emitter arrays with good uniformity and reproducibility.