Computer technology is developing extremely fast. There are new layouts and developments that must meet ever-increasing requirements. One of the most interesting things is the very large integrated circuit. What it is? Why does she have such a name? We know how VLSI stands for, but what does it look like in practice? Where are they used?
Development history
In the early sixties, the first semiconductor microcircuits appeared. Since then, microelectronics has come a long way from simple logical elements to the most complex digital devices. Modern complex and multifunctional computers can operate on a single semiconductor single crystal, the area of which is one square centimeter.
Should have had them somehowclassify and distinguish. Very large integrated circuit (VLSI) is so named because there was a need to designate a microcircuit, in which the degree of integration exceeded 104 elements per chip. It happened in the late seventies. Within a few years, it became clear that this was the general direction for microelectronics.
So, the very large integrated circuit is so named because it was necessary to classify all the achievements in this area. Initially, microelectronics was built on assembly operations and was engaged in the implementation of complex functions by combining many elements in one thing.
And then what?
Initially, a significant part of the increase in the cost of manufactured products was precisely in the assembly process. The main stages that each product had to go through are the design, implementation and verification of connections between components. The functions, as well as the dimensions of the devices that have been implemented in practice, are limited solely by the number of components used, their reliability and physical dimensions.
So if they say that some very large integrated circuit weighs more than 10 kg, it is quite possible. The only question is the rationality of using such a large block of components.
Development
I would like to make one more small digression. Historically, integrated circuits have been attracted by their small size and weight. Although gradually, with development, there were opportunities for ever closerplacement of elements. And not only. This should be understood not only as a compact placement, but also as an improvement in ergonomic indicators, an increase in performance and a level of operational reliability.
Special attention should be paid to material and energy indicators, which directly depend on the crystal area used per component. This largely depended on the substance used. Initially, germanium was used for semiconductor products. But over time, it was supplanted by silicon, which has more attractive characteristics.
What is being used now?
So we know that the very large integrated circuit is so named because it contains many components. What technologies are currently being used to create them? Most often they talk about the deep submicron region, which makes it possible to achieve the effective use of components in 0.25-0.5 microns, and nanoelectronics, where elements are measured in nanometers. Moreover, the first gradually becomes history, and in the second more and more discoveries are made. Here is a short list of developments that are being created:
- Ultra-large silicon circuits. They have minimum component sizes in the deep submicron region.
- High-speed heterojunction devices and integrated circuits. They are built on the basis of silicon, germanium, gallium arsenide, as well as a number of other compounds.
- Technology of nanoscale devices, of which nanolithography should be mentioned separately.
Although small sizes are indicated here, but there is no need to be mistaken about which one isultimate ultra-large integrated circuit. Its overall dimensions can vary in centimeters, and in some specific devices even meters. Micrometers and nanometers are just the size of individual elements (like transistors), and their number can be in the billions!
Despite such a number, it may be that an ultra-large-scale integrated circuit weighs several hundred grams. Although it is possible that it will be so heavy that even an adult will not be able to lift it on their own.
How are they created?
Let's consider modern technology. So, to create ultra-pure semiconductor single-crystal materials, as well as technological reagents (including liquids and gases), you need:
- Ensure ultra-clean working conditions in the wafer processing and transport area.
- Develop technological operations and create a set of equipment, where there will be automated process control. This is necessary to ensure the specified quality of processing and low levels of contamination. Although we should not forget about the high performance and reliability of the created electronic components.
Is it a joke when elements are created, the size of which is calculated in nanometers? Alas, it is impossible for a person to perform operations that require phenomenal accuracy.
What about domestic producers?
WhyIs the ultra-large integrated circuit strongly associated with foreign developments? In the early 50s of the last century, the USSR took second place in the development of electronics. But now it is extremely difficult for domestic producers to compete with foreign companies. It's not all bad though.
So, regarding the creation of complex science-intensive products, we can confidently say that the Russian Federation now has the conditions, and personnel, and scientific potential. There are quite a few enterprises and institutions that can develop various electronic devices. True, all this exists in a rather limited volume.
So, it is often the case when high-tech "raw materials" are used for development, such as VLSI memory, microprocessors and controllers that were manufactured abroad. But at the same time, certain problems of signal processing and computations are solved programmatically.
Although it should not be assumed that we can exclusively purchase and assemble equipment from various components. There are also domestic versions of processors, controllers, ultra-large-scale integrated circuits and other developments. But, alas, they cannot compete with the leaders of the world in terms of their effectiveness, which makes their commercial implementation difficult. But using them in domestic systems where you don’t need a lot of power or you need to take care of reliability is quite possible.
PLCs for programmable logic
This is a separately allocated promising type of development. They are out of competition in those areas where you need to createhigh-performance specialized devices focused on hardware implementation. Thanks to this, the task of parallelizing the processing process is solved and performance increases tenfold (when compared with software solutions).
Essentially, these ultra-large-scale integrated circuits have versatile, configurable function converters that allow users to customize the connections between them. And it's all on one crystal. The result is a shorter build cycle, an economic benefit for small-scale production, and the ability to make changes at any stage of the design.
Development of programmable logic ultra-large integrated circuits takes several months. After that, they are configured in the shortest possible time - and this is all at a minimum level of costs. There are different manufacturers, architectures and capabilities of the products they create, which greatly increases the ability to complete tasks.
How are they classified?
Usually used for this:
- Logical capacity (degree of integration).
- Organization of the internal structure.
- Type of programmable item used.
- Architecture of the functional converter.
- Presence/absence of internal RAM.
Each item deserves attention. But alas, the size of the article is limited, so we will consider only the most important component.
What islogical capacity?
This is the most important feature for very large scale integrated circuits. The number of transistors in them can be in the billions. But at the same time, their size is equal to a miserable fraction of a micrometer. But due to the redundancy of structures, logical capacity is measured in the number of gates that is needed to implement the device.
To designate them, indicators of hundreds of thousands and millions of units are used. The higher the value of logical capacity, the more opportunities an ultra-large-scale integrated circuit can offer us.
About the goals pursued
VLSI was originally created for fifth generation machines. In their manufacture, they were guided by a streaming architecture and the implementation of an intelligent human-machine interface, which will not only provide a systematic solution to problems, but also provide Masha with the opportunity to think logically, self-learn and draw logical conclusions.
It was assumed that communication would be conducted in natural language using a speech form. Well, in one way or another it was implemented. But still, it is still far from the full-fledged problem-free creation of ideal ultra-large integrated circuits. But we, humanity, are moving forward with confidence. VLSI design automation plays a big role in this.
As previously mentioned, this requires a lot of human and time resources. Therefore, to save money, automation is widely used. After all, when it is necessary to establish connections between billionscomponents, even a team of several dozen people will spend years on it. Whereas automation can do this in a matter of hours, if the correct algorithm is laid.
Further reduction seems problematic now, as we are already approaching the limit of transistor technology. Already, the smallest transistors are only a few tens of nanometers in size. If we reduce them by several hundred times, then we will simply run into the dimensions of the atom. Undoubtedly, this is good, but how to move forward in terms of increasing the efficiency of electronics? To do this, you have to go to a new level. For example, to create quantum computers.
Conclusion
Ultra-large-scale integrated circuits have had a significant impact on the development of humanity and the possibilities we have. But it is likely that they will soon become obsolete and something completely different will come to replace them.
After all, alas, we are already approaching the limit of possibilities, and humanity is not used to standing still. Therefore, it is likely that ultra-large integrated circuits will be given due honors, after which they will be replaced by more advanced designs. But for now, we all use VLSI as the pinnacle of existing creation.
