Deposition Tolerant Plasma Analysis In Motion

The Plato Spatial Probe is a Langmuir probe for deposition plasma. It scans across the bulk of a plasma to measure the uniformity of plasma parameters at different locations. It is designed to work in deposition plasmas even when an insulating layer is deposited on the probe surface.

The Plato Probe measures plasma parameters such as plasma density, ion current density and electron temperature at different locations across the plasma even when the plasma has a high deposition rate.

It is now possible to measure the uniformity of plasma parameters in a plasma depositing an insulating layer.

Overview

The Plato Spatial Probe comes complete with an automated linear drive system which measures the main parameters of plasma at different locations inside a plasma reactor. The Plato Spatial Probe is the first Langmuir probe on the market that can operate in a plasma with high deposition rates and key to its success is its ability to measure accurately the key plasma parameters through an insulating layer several microns thick. The deposition of insulating layers does not affect the accuracy of the probe's plasma characterisation.

The Plato Spatial Probe is a unique instrument enabling scientists to measure the electron density, Ion density, electron temperature and floating potential at different locations inside a plasma. The Plato Spatial Probe provides plasma parameter measurement in DC, RF, microwave, continuous and pulsed plasma. The Plato Spatial Probe has the most advanced patented technology on the market using ultra-fast biasing to penetrate the deposited film to obtain accurate characterisation of the real plasma parameters in a wide range of plasma applications.

The Plato Spatial Probe is used to establish plasma process repeatability, even in reactive gas plasma sometimes found in applications such as plasma enhanced chemical vapour deposition (PEVCD). It is the perfect instrument to understand plasma changes and the impact on surface treatment including plasma uniformity. Pulsed plasmas are used to tailor the electron or ion energy and the Plato Spatial Probe is an integral part of such a process development.

Plasma Parameters Measured

• Plasma Density Uniformity
• Ion Current Density Uniformity
• Electron Temperature Uniformity

Measurement Functionality

Time Averaged Measurements
This provides an average over time of the plasma parameters measured by the Plato Spatial Probe in the bulk of the plasma.

Time Resolved Measurements
This allows the user to synchronise the plasma parameters measured by the Plato Spatial Probe with an internal synchronisation signal. The user can then obtain detailed information on the plasma parameters as a function of time or phase through the synchronisation pulse period. Typically the pulse period would be on a timescale of milliseconds to microseconds.

Time Trend Measurements
This allows the user to obtain information on the variation of the plasma parameters as time progresses through a particular process. This feature does not require external synchronisation and the timescales involved can be in range of seconds to hours.