Ebeam technology is a direct writing technique that uses the accelerated beam of electrons to pattern features of nano to micro scale. Ideally, pattern transfer using the Electron Beam Technologies is achieved through use of a focused electron beam, that is serially exposed to the polymeric resist pixel-by-pixel, forming a custom pattern.
How Electron Beam Technology has Changed
The Electron Beam lithography systems started appearing in the late 1960`s. over the years, sizes down to 50 nm have been demonstrated. Today, the size of the minimum feature has been reduced to about 5 nm in principle, and uses the advanced EBL equipment.
Today, the electron beam technologies are considered as one of the techniques with the highest resolution. Ideally, the modern EBL systems are expensive and feature a high cost of maintenance. Consequently, there are just a few manufacturers of electron beam technology systems.
The EBL technique features a similar principle to the conventional lithography systems. Therefore, the EBL technique is based on just three steps, involving exposure of the sample surface, followed by developing the exposed area and finally transferring the pattern.
In EBL systems, both the positive and the negative photoelectron sensitive resists are used. Generally, the advantage of EBL systems includes precise control over the lateral dimensions down to the 5-7 nm level. In addition, the EBL lithography systems feature added flexibility in patterning of complex geometries. However, today’s EBL systems feature a slow patterning speed, which makes the mass production too expensive. Further, stitching errors create problems when patterning large areas.
The modern electron beam lithography resolution comes with the ability for precise control of patterning nanometer length scales. The EBL technique is a principal technique that is used for producing master templates used in the higher-throughput nanofabrication processes like the photolithography technique.
Generally, electron beam technologies and ion beam lithography have gone from a curiosity that grew following the advent of SEM. Today, the techniques are applied in the commercial mask making industry, and this dates back to the 1970s. Over the years, researchers have discovered the nanolithography capabilities and today rely on the adapted SEMs ideal for routine exploration of prototype devices at the nanoscale.
As of the 1980s, the EBL systems were first used in commercialized applications. However, the ebeam technology systems were too expensive and could only be afforded by the major research institutions. Following the rapid evolution of nanotechnology, the systems, materials, methods, and software for extraordinary levels of resolution and precise capabilities are available in the market.
Therefore, the ION beam technology and the electron beam technologies have a unique capability when it comes to making ever-more challenging devices and the structures possible. The two technologies have contributed substantially and fuel the imagination of researchers across the globe.
Electron Beam Melting Process
The electron beam melting process involves a thin layer of metal powder that is selectively melted using the electron beam technologies. The electron beam parts are built up layer by layer. Therefore, the electron melting process compares to the laser melting technology. However, the only difference is that the electron beam melting process does not feature the use of a laser. Therefore, the ebeam technology machine distributes a layer of metal powder onto the build platform, which is then melted by the electron beam. Ideally, the build platform is then lowered and the next layer of the metal powder is coated on the top. This process of coating powder and melting where needed is carried out repeatedly and the parts built up layer to another in the powder bed.
The electron beam melting process requires the support structures that anchor parts and overhanging structures to the build platform. Through this, the heat is transferred away from where the powder is melted. Consequently, the thermal stress is reduced and prevents wrapping.
The electron beam melting process is a technology that manufactures the parts in standard metals with a high density of above 99%. The technique features good mechanical properties that are comparable to the traditional production technologies. Therefore, compared to laser melting, the EBM produces less thermal stress in parts and so requires a less support structure. Besides, the process builds faster. The electron beam melting process is applicable in small series parts, prototypes, and support parts.