VLSI is a very complex field, There are various engineers required at each step of design. Let start with some broad picture
With in VLSI industry main technical fields are
2. Semiconductor Research
1. Development : These folks works on developing EDA tools which will be used for designing chips, companies like Cadence, Mentor Graphics and Synopsys are major players in this domains, People who has strong skills such as C, C++, data structure and algorithms usually enters into development. WIthin EDA engineers works on different tool development i.e. verification tools, infrastructure related automation tools, placement engine, STA (Static Timing Analysis), Extraction etc
2. Methodology Development : How to use tool and what options in tools are best suited for designer are fixed by these engineers, They usually create wrappers around tools so that life for designers becomes easy. TCL (tool command language) Perl , Shell scripting are major skills required for this job. Within methodology there are different areas like Routing, Placement, Synthesis, STA and Signoff.
3. Application Support (Also known as Application Engineer) : These engineers directly works with designers on implementing chip, They help designer in better understanding of tools, work with development team on implementing new features and communicate problems reported in field to development side. Field Application engineer often travels to customer location to work with them.
4. Product Engineer : Product Engineer is special category of engineer who are responsible for entire product. They are expected to know In and Out of a EDA tool, Basically they are first point of contact for any tool issues, They work with development on creating a solution for common problems. These guys often travels to customer location to prove their tools are better than any other vendor tools (also known as benchmarking)
5. Tool Testers or Validation Engineers : These guys makes sure that each tool comes out of EDA industry is tested well enough, They work as pseudo designers and make sure tool shipped outside EDA is of good quality, They usually work on automating testing flow, it’s like software testing but with knowledge of VLSI Chip designing.
Semiconductor Research : This is a very broad area to start with usually engineers in this field work in developing next generation technology node, New technologies like finFET, SOI comes from this team, They mainly deal with fab and runs simulations what effects of changing certain dopent has on chip or manufacturing process, They create models for foundary which later on used as rules for standard cell characterization.
Design : Design field consist of following major roles
1. Logic Designer : This person is solely responsible for Designing logic in VHDL, Verilog or any other proprietary language. Sometime company expects these designers to perform logic synthesis on designs that they are working on.
Companies like Cadence, Synopsys are acquiring IP design companies to increase their own IP porfilio, IPs are usually like USB interface, Ethernet connection, PCI Express etc. These IPs keep updating based on new technology nodes as well as latest changes
2. Physical Design : There are various aspects of Physical Design it starts from Synthesis and goes upto post sign off checks. There are various steps involved in between such as Placement, Synthesis, STA (at each step), Routing, Post Routing optimization, Extraction, PDV (Physical Design Verification) Checks.
There are various sub domains such as analog design, mixed signal design, Digital design implementation, SRAM or memory cell development. Primary job for everyone is to meet frequency requirement and make design manufacturable by adhering to all design rules set to specific technology and foundary.
3. Standard cell design : For digital design standard cells such as NAND, NOR, NOT etc gets developed based on various foundary specifications such as TSMC, Common Platform, Global Foundary etc. Every company probably develops it’s own form on standard cells, designer work on layout creating NAND, NOR etc. There are different VT levels gets crated based on design complexity.
4. Verification : I am considering verification as part of design as it’s just another aspect of design cycle, Verification Engineer provides pseudo inputs and trigger to verify functionality of design, (Remember they don’t care about frequency here frequency is going to meet or not is job of Physical Design Engineers) Vera, OVM, VHDL, Verilog languages are used in this domain, IP verification is another area demand these days.
Manufacturing : I have very limited knowledge in this field but essentially these are engineers who works on developing masks, and manufacturing chips, There are various phases in which they test these chips, There are people who works on integrating and packaging chip. Probably building system, PCB and boards also comes under this field.