Method of fabricating electric field sensor having electric field shield
View Patent ↗A method of manufacturing an electric field sensor having an electric field shield. The method includes providing a substrate doped with a first impurity; forming a resistive tip having a resistance region doped with a low concentration of a second impurity at an apex of a protruding portion of the substrate, and first and second semiconductor electrode regions doped with a high concentration of the second impurity on both slopes of the protruding portion with the resistive region therebetween, wherein the second impurity has a polarity opposite to that of the first impurity; forming a dielectric layer on the resistive tip; forming a mask having a high aspect ratio on the dielectric layer; depositing a metal layer on the dielectric layer; and exposing the dielectric layer formed on the resistance region through the metal layer by removing the mask.
1. A method of manufacturing an electric field sensor having an electric field shield, comprising:
providing a substrate doped with a first impurity;
forming a resistive tip having a resistance region doped with a low concentration of a second impurity at an apex of a protruding portion of the substrate, and first and second semiconductor electrode regions doped with a high concentration of the second impurity on both slopes of the protruding portion with the resistive region therebetween, wherein the second impurity has a polarity opposite to that of the first impurity;
forming a dielectric layer on the resistive tip;
forming a mask having a high aspect ratio on the dielectric layer;
depositing a metal layer on the dielectric layer; and
exposing the dielectric layer formed on the resistance region through the metal layer by removing the mask.
2. The method of claim 1 , wherein the mask has an aspect ratio of at least 3:1.
3. The method of claim 1 , wherein the forming of the mask comprises depositing the mask using a focused ion beam (FIB) system.
4. The method of claim 1 , wherein the mask has an upper diameter greater than a lower diameter thereof that contacts the dielectric layer on the resistance region.
5. The method of claim 1 , wherein the forming of the mask comprises forming the lower diameter of the mask that contacts the dielectric layer to 10 to 100 nm.
6. The method of claim 1 , wherein the mask is formed of a material selected from carbon, tungsten, platinum, silicon oxide, and silicon nitride.
7. The method of claim 1 , further comprising exposing the resistance region by etching the dielectric layer on the resistance region exposed through the metal layer.
8. The method of claim 1 , wherein the forming of the dielectric layer comprises depositing the dielectric layer having a first thickness on the resistance region.
9. The method of claim 1 , wherein the mask is formed to correspond to the resistance region.