Extensive Computer Simulations Could Improve Microchip Production Techniques

Materials Studio

Microchips have come a long way, but researchers have hit a plateau using current assembly techniques. Image Source: Flickr User: tico_24

Computers and microchips have come a long way in the last few decades. Unfortunately, on the road to progress, researchers and developers are hitting a speed and computing power plateau. There are a number of physical limitations based on the techniques used to create microchips, and either the materials or procedures need to be modified to enable progress. A new technique involving block copolymer self-assembly may allow manufacturers to produce smaller, more powerful microchips.1 Modern lab software will help researchers continue to develop new techniques and materials to ensure that innovation does not taper off.

Within the Wires

Microchips, or integrated circuits, are composed of a set of electronic circuits, including transistors, on a semiconductor chip. After the production of a wafer of semiconductor material, normally silicon, it must undergo roughly 1500 steps in a clean room before becoming a useable chip. Through a process called photolithography, the wafer is coated with photosensitive chemicals which react in the presence of UV light. In a darkroom, an image of a circuit design is projected onto a portion of the wafer causing a circuit to solidify. When the excess photosensitive chemicals are rinsed from the surface, the circuit remains in a similar manner to film photo development and printing. Alternatively, lithography may be performed using a concentrated ion or electron beam; however, this is more expensive. The lithography provides the groundwork for the remainder of the chip.

To assemble the rest of the circuit, the chip undergoes similar processes to lithography with upwards of 40 designs to inlay the entire circuit. Some layers are cooked, some are blasted with ionized plasma, some are bathed in metals. Each process incites different properties creating the many different components of different types of chips.2 The techniques classically used to create microchips, while superb, have some inherent limitations which are actively contributing to stagnation:

  • Chemical Properties. Most liquids can only form layers that are so thin. This limits the ability to reduce the packing of components of the chip. Innovative lab software can be employed to further investigate the properties of these chemical precursors. Perhaps, through in depth chemical investigation and innovation, the properties can be modified.
  • Wavelength of Light. The photolithographic technique described above relies on UV light, which has a specific wavelength range. If you want smaller components, the wavelength needs to be smaller. Generating shorter wavelength light is much more expensive, driving the cost too high to be feasible.
  • Time and Cost. Yes, manufacturers have developed a way to create smaller circuitry, line by line, by scanning a beam of electrons or ions across the surface of the chip. But this is a  ludicrously slow and expensive process. Until technology to reduce light wavelength has been developed and price has dropped, it is not a viable solution; nor is the use of electron or ion beams, alone.

Reassessing the chemicals used with modern lab software is the most logical route. Fortunately, since microchips started being produced in the ‘60s, technology has come a long way. With a comprehensive suite of predictive and modelling software, circuit precursors can undergo in depth investigation and redevelopment. Thereafter, the procedures and processes can be modified, in silico, accordingly.

Self-Assembling Miracle

Recently research may have yielded a less expensive, scalable alternative to tackle this power roadblock. This research hinged on the integration of three existing methods:

  • Lithography. The researchers used an electron beam to etch the pattern into the surface of the chip.
  • Block Copolymers. Researchers deposited a mix of two different polymer materials onto the surface of the chip. This polymer combo contains lipophilic and hydrophilic compounds that naturally segregate themselves into predictable patterns. In essence, they’re preprogrammed to form very particular shapes of particular dimensions. These polymers can be modelled/programmed with the aid of modern lab software.
  • Initiated Chemical Vapor Deposition (iCVD). The final, protective polymer layer is applied using iCVD, wherein the polymer combination is heat or pressure vaporized and subsequently forms layer on the colder substrate.3 This is the pièce de résistance: it constrains the assembly of the block copolymers forcing them into vertical layers which allows for more efficient packing of the circuitry.4

This process may help researchers and manufacturers clear the power hurdle in a convenient and affordable way. Many companies already some form of lithography and iCVD is well understood and already implemented at some facilities. These two steps would be straightforward to add to most cleanrooms, as the infrastructure is there in many cases. Modern lab software could ease the transition from classic methods by holding information about materials and standard operating procedures. It is of note that this process would be less expensive than advanced optics of a fully electron-beam based system.

BIOVIA Materials Studio is the missing key to rapidly advancing your microchip development. With extensive computer simulations, you can save both time and R&D funds. Novel materials and the repurposing of methods have advanced this research and show promise to overcome this technological hump. Using this novel information in combination with computer modelling capabilities can help to steer your research towards a deliverable product, faster. Please contact us today to learn more about how our software options can support the efforts of your lab.

  1. “A big leap toward tinier lines,” March 27, 2017, http://news.mit.edu/2017/self-assembly-smaller-microchip-patterns-0327
  2.  “How Microchips are Made,” October 13, 2010, https://www.youtube.com/watch?v=F2KcZGwntgg
  3. “Explained: chemical vapor deposition,” June 19, 2015, https://news.mit.edu/2015/explained-chemical-vapor-deposition-0619
  4. “Sub-10-nm patterning via directed self-assembly of block copolymer filsm with a vapour-phase deposited topcoat,” March 27, 2017,  https://www.nature.com/nnano/journal/vaop/ncurrent/full/nnano.2017.34.html