High Curie Point Piezoelectric Film for High-Temperature Solder Ejection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional inkjet marking heads are limited by their Curie point, which restricts their operation to room temperature, making them unsuitable for high-temperature applications like solder patterning on electronic components, as they depolarize or become ineffective when heated, necessitating reflow treatment that can damage components.
Innovation Solution
A liquid ejection device with a piezoelectric film having a Curie point of 200° C. or more, allowing operation at high temperatures and enabling the ejection of solder materials in the liquid phase without the need for reflow treatment, using a thin-film piezoelectric material with a columnar crystalline structure and a heating means to maintain the material above its melting point.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If conventional piezoelectric materials with Curie point of at most 140°C are used, then the device can operate at room temperature, but the device cannot be used at high temperatures above the Curie point
Solution Approach 1:
The patent changes the fundamental parameter of the piezoelectric material's Curie point from conventional values (at most 140°C) to a high Curie point of 200°C or more. This parameter change enables the piezoelectric device to maintain its functional properties at elevated temperatures, allowing operation in high-temperature environments such as soldering processes without loss of piezoelectric performance.
Solution Approach 2:
The patent employs composite material structures including the piezoelectric layer combined with heating elements and temperature control systems. This composite approach allows the device to actively manage temperature conditions, maintaining operation within the piezoelectric material's effective range while enabling the overall system to function in high-temperature environments.
2Manufacturing precision
If solder paste is used requiring reflow treatment, then solder connections can be formed, but electronic components may be damaged by high temperature heating
Solution Approach 1:
The patent replaces the conventional thermal reflow process with a mechanical/electrical ejection mechanism. The piezoelectric device uses electric field-induced mechanical deformation to eject molten solder directly through the nozzle, substituting the thermal reflow process with a controlled mechanical ejection process that requires minimal or no heating of the substrate and components.
Solution Approach 2:
The patent performs preliminary melting of the solder material in the pressurized liquid chamber before ejection. The heating element melts the solder in advance within the chamber, and then the piezoelectric device ejects the pre-melted solder onto the substrate. This preliminary action eliminates the need for high-temperature reflow treatment of the entire substrate and components.
3Reliability
If conventional inkjet heads operate at room temperature, then piezoelectric materials function reliably, but they depolarize or become ineffective when heated
Solution Approach 1:
The patent fundamentally changes the temperature parameter threshold of the piezoelectric material by selecting materials with Curie points of 200°C or more. This parameter change shifts the depolarization threshold to a much higher temperature, allowing the material to maintain its piezoelectric properties and effectiveness in high-temperature environments where conventional materials would fail.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables precise solder patterning at high temperatures without damaging electronic components, reducing production steps and eliminating the need for reflow treatment, while maintaining sufficient piezoelectric performance even at elevated temperatures.
Implementation Method 1
a piezoelectric device, which includes a piezoelectric layer having piezoelectricity to expand or contract along with increase or decrease of the intensity of an electric field applied thereto
Implementation Method 2
a heating means for heating a material charged in the pressurized liquid chamber, the material having a melting point of not less than 150° C. and lower than the Curie point of the piezoelectric film, the heating means heating the material to a temperature not less than the melting point of the material
Implementation Method 3
the piezoelectric film being a thin-film piezoelectric material having a Curie point of 200° C. or more
Data Source
AI summary
A liquid ejection device includes a liquid ejection member including a pressurized liquid chamber and a liquid ejection orifice which is in fluid communication with the pressurized liquid chamber to eject a liquid in the pressurized liquid chamber to the outside. A piezoelectric device is formed on the pressurized liquid chamber via a vibrating diaphragm. The piezoelectric device includes a lower electrode, a piezoelectric film and an upper electrode, which are disposed sequentially. The piezoelectric film is a thin-film piezoelectric material having a Curie point of 200° C. or more. The liquid ejection device further includes a heating element for heating a material, which has a melting point of not less than 150° C. and lower than the Curie point of the piezoelectric film, charged in the pressurized liquid chamber to a temperature not less than the melting point of the material.