John Morris

Overview

A pressure-based measurement and control system to meter and control vapor from low vapor pressure liquid and solid sources.

A need exists in thin film processes to deliver solid precursors to CVD reactors in a precisely controlled manner. Currently, the only commercially available method to deliver solids is using solvent/solute chemistries with liquid delivery methods (i.e. liquid flow meters or direct liquid injection). A limitation of liquid delivery methods is that some solid precursors have solubility limits which restrict the maximum precursor mass flow that can be delivered to the process chamber.

MKS has developed the 1153A Low Vapor Pressure Source Delivery System to deliver controlled amounts of vapor from a solid source or low vapor pressure liquid source precursor to the process chamber at rates consistent with high throughput requirements.

The 1153 Low Vapor Pressure Source Mass-Flo Controller is a pressure-based measurement and control system designed to meter and control vapor from low vapor pressure liquid and solid sources directly, without the need for a carrier gas. The flow of vapor is controlled via pressure-based techniques using two Baratron® pressure transducers, a flow orifice, and a high temperature solenoid valve. Tight temperature control is possible using a thermally optimised heater block design.
Features

• Delivers low vapor pressure liquids and solids without the need for a carrier gas system, for precise, repeatable vapor source delivery
• High operating temperature up to 200°C
• On-board CPU allows for control of flow over a wide range
• Control of flow via analog (0-5 VDC) or RS-232 offers flexibility and diagnostic capabilities
• All metal internal CF-style seal design eliminates contamination due to permeation of elastomeric seals
• Maximum flow (process dependant): 10 slm with 760 Torr inlet to a 10 Torr process allows for high throughput

Benefits

The MKS Type 1153 Low Vapor Pressure Source Mass-Flo Controller is a pressure-based measurement and control system designed to meter and control vapor from low vapor pressure liquid and solid sources directly, without the need for a carrier gas. The flow of vapor is controlled via pressure-based techniques using two Baratron® pressure transducers, a flow orifice, and a high temperature solenoid valve. Tight temperature control is possible using a thermally optimised heater block design.