Fabrication of a Silicon Electron Multiplier sensor using Metal Assisted Chemical Etching and its characterisation

TL;DR

This paper presents a novel Silicon Electron Multiplier sensor fabricated using Metal Assisted Chemical Etching, demonstrating its compatibility with active media and p-n junctions through electrical characterization.

Contribution

It introduces a new fabrication method for SiEM sensors using MacEtch, enabling high-aspect-ratio silicon structures for charge multiplication.

Findings

Successful fabrication of silicon pillars exceeding 10 μm in height.

Electrical tests confirm process compatibility with active media.

Demonstrated charge multiplication potential in SiEM sensors.

Abstract

The Silicon Electron Multiplier (SiEM) sensor is a novel sensor concept that enables charge multiplication by high electric fields generated by embedded metal electrodes within the sensor bulk. Metal assisted chemical etching (MacEtch) in gas phase with platinum as a catalyst has been used to fabricate test structures consisting of vertically aligned silicon pillars and strips on top of a silicon bulk. The pillars exceed 10 $\mu m$ in height with a diameter of 1.0 $\mu m$ and are arranged as a hexagonal lattice with a pitch of 1.5 $\mu m$. Electrical characterisations through current $-$ voltage measurements inside a scanning electron microscope and a climate chamber have demonstrated that the MacEtch process is compatible with active media and p-n junctions.