Microlithography is a manufacturing process used to create an infinitesimally small patterned film that protects a substrate. This process is mainly used in the semiconductor industry. Advanced microlithography process materials include nanoimprinting, interface lithography, Photolithography, and electron beam lithography.
However, this article focuses on two types: Photolithography and electron beam lithography. You will know all the tips about both processes in this article. And finally, this article will help you decide the better process between the two.
Photolithography is how light transfers shapes from a photomask or template to a surface. This process is used because of its ability to make accurate precisions. Photolithography requires perfect temperature conditions and a clean substrate surface because it is a highly complex process. It is primarily used in micro-manufacturing applications and can only manufacture flat surfaces. Also, Photolithography is arguably the most popular process to produce integrated circuits.
How Does Photolithography Work?
To use Photolithography, you have to clean the substrate you want to use with clean water or any other chemical. Then you will coat the substrate with a chemical that is sensitive to light. After which, you will expose the coated substrate to a focused beam of ultraviolet light. The ultraviolet light will dissolve the parts of the exposed substrate, and a pattern will be formed. This new pattern will then transfer electricity from one part of the substrate to another.
There are different applications of Photolithography. They include but are not limited to:
- Production of integrated circuits
- Production of internal computer parts
- Production of nanites and microcomputers
- Production of patterns on micro surfaces
Advantages of Photolithography
Like every other advanced microlithography process material, Photolithography has its advantages. Some of them are:
- It can form a pattern in an integrated circuit using only a single ultraviolet light beam.
- It is cost-effective and highly efficient
- It takes control of the shape and size of the substrate.
Disadvantages of Photolithography
Some disadvantages of Photolithography are:
- For Photolithography to produce effective patterns, it requires an entirely flat surface.
- It also requires an extremely clean substrate.
- The substrate must not be contaminated and also be void of liquids.
Electron Beam Lithography
Electron Beam Lithography is the process of scrutinizing an intense beam of electrons to draw custom patterns on a coated electro-sensitive film surface called a resist.
Electron Beam Lithography: How it works
To use EBL, a sample will be coated with a thin layer of resistance called polymethylmethacrylate(PMMA) and exposed to a beam of electrons. After exposure, PMMA will break down into monomers, and the exposed areas will be washed with a chemical. Although, the process might seem simple. The EBL process is complex and very slow when compared to Photolithography.
Electron Beam Lithography Applications
Electron beam lithography has two main applications, and they are:
- To achieve high-resolution lithography
- Production of masks through the etching process
Advantages of Electron Beam Lithography
There are different advantages of EBL, and some of them are:
- EBL is a flexible process
- It has a high resolution that can be up to 2onm
- EBL can print complex patterns on the wafers directly.
- It is highly efficient when it comes to eliminating diffraction problems
Disadvantages of Electron Beam Lithography
As much as electron beam lithography has many advantages, it also has disadvantages. Some of the disadvantages of electron beam lithography are
- EBL only use secondary electrons
- EBL process is highly complex and slower than Photolithography
- Electron Beam Lithography is complicated and very expensive
- It contributes a lot to backscattering
- EBL also has forward scattering.
Advanced microlithography process materials are prevalent in the semiconductor industry. There are also several types of these processes with various applications and advantages. However, with this article, you can understand what Photolithography and Electron-beam Lithography are, their applications, how they work, advantages and disadvantages. Now that you have a quantifiable knowledge of the two processes, you will be able to choose between the two of them quickly. Also, although electron beam lithography is complex and involves a much slower process than Photolithography, it is more popular and widely used in different applications.