There can be only two reasons why you landed on this page. First, you want to know who I am, or you want to actually get into VLSI. Either way, let's jump in.
Why even bother?
So electronics have long been a sort of "keystone" to all other technologies. From your desktop computers to the data centers running some of the most advanced AI models, all of them boil down to electronics.
So that's how crucial electronics actually are. And since we are talking about VLSI, which is such a vast field, let's take a 15,000-foot view of this field.
What is it?
VLSI stands for Very Large scale integration. Integration of what exactly? Transistors. Integration on what? Silicon and how? Well, that's exactly what VLSI is.
Pre-requisites
So let's talk about prerequisites.
First, Digital electronics.
Knowledge of number representation, codes such as binary code, gray codes, and XS-3, how gates are built and how they function, various combinational and sequential circuits, finite state diagrams, and sequence detectors are some of the concepts that set the baseline for studying VLSI.
Second, Analog Electronics.
Various analog circuits, biasing techniques, BJT amplifiers, MOS amplifiers, oscillators, and Operational amplifiers are some of the concepts that need to be studied before diving into advanced concepts related to VLSI.
Third, Programming Concepts.
Object Oriented Programming using C++, Verilog, and bash scripting. That’s it.
Actually getting in
There are multiple ways, actually, to get in. The first one is for those who are in their bachelor’s, studying Electrical or Electronics engineering.
The second one is for those who either have some work experience or feel unsatisfied with the knowledge they acquired in their undergraduate studies.
For undergrads
Give all your attention to core electronics subjects. Digital electronics, Analog electronics, Control systems, and VLSI design.
Some colleges are generous enough to teach digital VLSI design and analog CMOS design in undergrad, give all your focus to these subjects, and play as much as you can with the tools that are being taught.
For Graduates
Being from a so-called “tier-3” college, this is the path that I personally took. Attempt GATE and secure admission to a reputable college with a curriculum tailored for both research and industry. It was the most approachable and streamlined predetermined approach for me.
If you can study on your own while working, a couple of hours a day should be enough to get you up and running for projects that can showcase your ability in the field.
If you are willing to take a break and it is financially viable for you, consider pursuing a master's degree. I would highly recommend taking a master's course in a reputable college with a strong curriculum, both for industry and research.
I can’t personally vouch for any college except mine, but IITs, IIITs, and NITs do provide some of the best VLSI and microelectronics courses in India; this is a known fact.
If these are out of options, I would rather recommend you choose a better college abroad. Again, this is not my area of expertise, but there are many people who can assist you. There are numerous scholarships and programs available to help you gain admission to such universities.
Now these were the two paths. The curriculum remains the same. Let's take a closer look.
Digital IC Design
In digital electronics, if you are comfortable with an undergrad level or basic digital electronics, you can start with CMOS digital design.
For this, start with MOSFETs, short channel effects like Velocity saturation, DIBL and GIDL, CMOS inverter (MOST important), its Voltage transfer characteristics, noise margin, Delays, and Power.
For practical knowledge of this subject, universities usually provide a lot of industry-grade tools, such as Cadence EDA Suite. However, if you still need some open-source alternatives, I would recommend Ngspice for schematics and Magic Layout. Although they are not industry standards, and cadence and synopsis tools remain the primary choice for the industry, these open-source tools can give you a lot of great hands-on experience.
Analog IC Design
Before starting Analog IC design, you should be comfortable with BJT Amplifiers, MOS amplifiers, and op-amp circuits.
MOS Circuits, current sources, current sinks, differential amplifiers, opamps, and their design, frequency response, and dominant poles.
The most crucial distinction between this and analog electronics that you studied in undergrad is the focus on MOS circuits.
For analog IC design, we again typically use the same tools as digital IC design.
In my opinion, it would be best not to pursue any kind of layout in analog IC design, as the subject primarily focuses on analog circuits and their design, and the layouts can be quite complex for someone just starting.
VLSI Design Flow
This is another important subject. This is the part where we go through the entire flow of making a chip. From ideation to actual fabrication of the silicon.
This includes logic synthesis, software hardware partitioning ( meaning which part of the algorithm needs to be implemented in hardware ), verification through various methods, ultimately providing a detailed view of the entire process, from writing RTL code to creating a GDS.
The entire flow utilizes a series of both open-source and closed-source tools that you can choose from based on your requirements.
For this, I have an exhaustive list of open-source tools available. You can either check out on my Instagram handle, or I’ll be posting them here anyway in the coming weeks.
Conclusion
As a conclusion, I would like to add that in no means is this an exhaustive roadmap to getting into VLSI design. But I do firmly believe that this is something that would have helped me greatly when I was wondering how to get started.
And VLSI, in itself, is a vast field. So extensive that it is almost impossible to cover the entire, detailed process of even one subject in a single blog post. Well, that’s why I am here. I will be (or at least try) posting a blog every week, breaking down concepts, bringing out research, and occasionally sharing my insights here. Stay tuned for them.
You can follow me on Instagram and Twitter.
Anyways… Happy Learning.