A 128-channel picoammeter system and its application on charged particle beam current distribution measurements

TL;DR

This paper presents a 128-channel picoammeter system with high resolution for charged particle beam current distribution measurements, demonstrating its effectiveness with ion and electron beams.

Contribution

A novel 128-channel picoammeter system utilizing instrumentation amplifiers for precise beam current distribution measurements.

Findings

Achieved current resolution better than 5 fA.

Successfully measured ion and electron beam distributions.

Provided accurate boundary detection for charged particle beams.

Abstract

A 128-channel picoammeter system is constructed based on instrumentation amplifiers. Taking the advantages of high electric potential and narrow bandwidth in DC energetic charged beam measurements, current resolution better than 5 fA can be achieved. Two 128-channel Faraday cup arrays are built, and are employed for ion and electron beam current distribution measurements. Tests with 60 keV O3+ ions and 2 keV electrons show that it can provide exact boundaries when a positive charged particle beam current distribution is measured.