Who is Mapper?
Mapper designs and produces machines that are used for the production of computer chips (integrated circuits or IC’s). The production of IC’s consists of multiple consecutive processes for which different machines are required. The machines of Mapper are dedicated specifically to writing line structures on the IC’s. Writing these structures is a complex process, especially since the size of IC’s has reduced significantly over the years, to about the size of a peppercorn. The structures that have to be written on these IC’s are a lot smaller, almost a thousand times thinner than a human hair.
Masks and the limitations of light
In general, light is used to write these structures. This process is called photolithography. In order to apply structures on an IC a template is made, a so called mask. This mask is then placed between the light source and the IC. The light will be transmitted through the mask to the IC. In combination with a lens system a strongly demagnified image of the structure that is on the mask will be applied to the IC. This process will have to be repeated multiple times. To create a fully functional IC, multiple layers have to be applied. Every layer requires a separate mask. Complex chips have more than 60 layers and therefore require the same amount of masks. The manufacturing of masks is a technically complex and expensive process. It is therefore not surprising that the lithography step is the most expensive in the manufacturing process of IC’s.
Another aspect of photolithography is that it is faster than other mature IC production processes. But a disadvantage of light is that the resolution (amount of detail) of the pattern is limited by the wavelength of the light that is used. This limit has been reached in the mean time. Continuing efforts are being done to further advance the shrinking process with ultra advanced techniques, but their application, masks and the machines are extremely expensive.
Mapper: volume production with electrons.
The approach Mapper is taking is radically different. To write structures, Mapper is not using light but electron beams. This technology is called electron lithography. The advantage of electron beams is widely known: the resolution, focus depths and flexibility are unmatched.
The most important characteristic of the Mapper machine is that it can manipulate these electron beams individually so that it can write the structure directly without a mask. The structure can be created with a computer after which it can be applied to the IC at Nano-scale. Because a mask is not required, the startup costs of a new design will be significantly lower.
Complementarity of Mapper
What makes it interesting is that both technologies can be used side by side to complement each other. This will produce new applications, even in existing production processes. Chip manufacturers can create new applications in existing processes with Mapper: for example reduce the resolution of a single critical circuit, increase the capacity of a piece of integrated memory or increase the focal depth in difficult layers, improving integration of different function types, or even make certain layers obsolete.