What Is a Microfabrication Machine?
A microfabrication machine is a processing machine that performs micron-level microfabrication. They are not limited to processing metals, but also process resins, polymers, and inorganic materials.
In recent years, there are cutting machines that can be programmed and controlled at the 10-nm level, and the scale of microfabrication is advancing daily.
Microfabrication machines in the broad sense of the term also include electric discharge machines, wire EDMs, jig borers, and laser cutting machines. In handling these microfabrication machines, temperature control such as room temperature and operator skill are also very important.
Uses of Microfabrication Machines
In recent years, microfabrication technology has become necessary in all industrial fields and is used in a wide range of applications.
In the semiconductor and electronic components industries, it is essential for processing package molds and various parts as devices become finer and finer, and in the medical equipment industry, it is essential for parts with micro flow paths such as biochips and parts with fine electrode structures.
It is possible to realize microstructures that cannot be machined with conventional end mills, such as heat dissipating fins with extremely small pitch, holes with micron-order pitch, and projection array structures with submicron-order pitch.
Principle of Microfabrication Machines
Microfabrication machines, in the broad sense, encompass multiple types of machines, but there are three representative types of machines. There are microfabrication machines, electrical discharge machines, and wire EDM machines, each of which has different principles.
1. Microfabrication NC Machine
Although the basic structure and principles are much the same as those of conventional NC machining centers, high-precision control is applied to all aspects of the machine, including the drive method for each axis, coolant temperature control, and rotation speed control.
Linear motors are used to drive each axis, and some products have a programmed resolution of 0.1 nm. Hydrostatic guiding is used for the guides that control the reciprocating motion, which enables infinitely low frictional resistance and high motion accuracy.
Coolant, which manages the heat generated during processing, is temperature-controlled at the 1/100°C level, and to block various vibrations transmitted from outdoors, anti-vibration measures are taken from the building foundation structure, or the building is installed on a vibration isolation system. In addition, the coolant is installed in a constant-temperature room to prevent thermal expansion of the equipment.
2. Electrical Discharge Machining Center
For microfabrication of conductive materials, an electric discharge machine with an anode connected to the material side and a cathode connected to the movable electrode is used. This technology of machining with direct current is used for materials and shapes that are susceptible to machining strain from cutting and polishing, and enables higher precision and surface roughness through repeated machining.
3. Wire Electric Discharge Machine
The basic principle is the same as that of EDM, but a cathode is connected to a very thin wire of about 0.05 to 0.3 mm, and a DC current is applied between the wire and the material to cut the material. Processing is performed in water with controlled conductivity, and the wire is constantly fed during processing. Since the cutting is done in a non-contact, stroke-by-stroke manner, no processing stress is generated. It is possible to cut a wire thickness plus 20 to 30 microns.
Other Information on Microfabrication Machines
Machines Used in Combination With Microfabrication Machines
Machines used in combination with microfabrication machines require a high degree of precision and stability. In order to support microfabrication, the machine itself must be highly accurate and the machining conditions must be set appropriately. It is necessary to understand the characteristics of each machine and select the optimum machine.
Here, we introduce three types of typical machines used in conjunction with microfabrication machines: laser cutting machines, electron beam machines, and ion beam machines.
- Laser Processing Machine
Laser processing machines cut and process materials by irradiating high-energy laser beams. They are suitable for microfabrication and can be used for a variety of materials, both metallic and non-metallic. They are also highly accurate and can handle minute processing. - Electron Beam Machine
Electron beam machines cut and process materials by irradiating heated electron beams at high speed. They are suitable for microscopic processing and are used in fields that require high processing accuracy. - Ion Beam Machines
Ion beam machines can perform microfabrication and surface modification of material surfaces by irradiating ion beams. This is especially effective for hard materials such as ceramics and glass.