A scanning microscopy technique based on capacitive coupling with a field-effect transistor integrated with the tip

作者：Shin Kumjae; Kang Dae Sil; Lee Sang Hoon; Moon Wonkyu^*

来源：Ultramicroscopy, 2015, 159: 1-10.

DOI：10.1016/j.ultramic.2015.07.007

• Scanning probe microscopy
• Metal-oxide-semiconductor transistor
• Surface electric field
• Amplitude modulation
• Local capacitance

We propose a method for measuring the capacitance of a thin layer using a Tip-on-Gate of Field-Effect Transistor (ToGoFET) probe. A ToGoFET probe with a metal-oxide-semiconductor field-effect transistor (MOSFET) with an ion-implant channel was embedded at the end of a cantilever and a Pt tip was fabricated using micro-machining. The ToGoFET probe was used to detect an alternating electric field at the dielectric surface. A dielectric buried metal sample was prepared; a sinusoidal input signal was applied to the buried metal lines; and the ToGoFET probe detected the electric field at the tip via the dielectric. The AC signal detected by the ToGoFET probe was demodulated by a simple AC-to-DC converter. Experimentally, it was shown that an electric field could be measured at the surface of the dielectric layer above a buried metal line. This promising result shows that it is possible to measure the surface local capacitance.

• 出版日期2015-12