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What are the steps required to solve setup and Hold violations in VLSI Explain?

There are few steps that has to be performed to solved setup and hold violations in VLSI. The steps are as follows:
the optimization and restructuring of the logic between the flops are carried way. This way logics are combined and it helps in the solving this problem.
There is way to modify the flip-flops that offer lesser setup delay and provide faster services to setup a device.
Modifying the launch-flop to have a better hold on the clock pin, which provides CK->Q that makes the launch-flop to be fast and helps in fixing setup violations.
The network of the clock can be modified to reduce the delay or slowing down of the clock that captures the action of the flip-flop.
There can be added delay/buffer that allows less delay to function that is used.

What are the different ways in which antenna violation can be prevented Explain?

Antenna violation occurs during process of plasma etching in which charges generating from one metal strip to another gets accumlated at a single place. The longer the strip the more the charges gets accumulated. The prevention can be done by following method:
Creating a jogging the metal line, that consists of atleas one metal above the protected layer.
There is a requirement to jog the metal that is above the metal getting the etching effect. This is due to fact that if a metal gets the etching then the other metal gets disconnected if the prevention measures are not taken care.
There is a way to prevent it by adding the reverse Diodes at the gates that are used in circuits.

What is funciton of tie-high and tie-low cells?

Tie-high and tie-low are used to connect transistors of the gate by using either the power or the ground. The gates are connected using the power or ground then it can be turned off and on due to power bounce from the ground. The cells are used to stop the bouncing and easy from of the current from one cell to another. The cells are required Vdd that connects to the tie-high cell as there is a power supply that is high and tie-low gets connected to Vss. This connection gets established and the transistors function properly without the need of any ground bounce occuring in any cell.

What is the main function of metastability in VSDL Explain?

Metastability is an unknown state that is given as neither one or zero. It is used in designing system that violates the setup or hole time requirements. The setup time requirement need data to be stable before the clock-edge and the hold time requires data to be stable after the clock edge has passed. There are potential violation that can lead to setup and hold violations as well. The data that is produced in this is totally asynchronous and clocked synchronous. This provide a way to setup the state through which it can be known that violations that are occuring in system and a proper design can be provided by use of several other functions.

What are steps involved in preventing the metastability?

Metastability is the unknown state and it prevents theof violations using the following steps:
proper synchronizers are used that can be two stage or three stage whenever the data comes from the asynchronous domain. Thus helping in recovering the metastable state event.
The synchronizers are used in between cross-clocking domains. This reduces the metastability by removing the delay that is caused by data element that are coming and taking time to get removed from the surface of metal.
Use of faster flip-flops that allow the transaction to be more faster and it removes the delay time between one component to another component. It uses a narrower metastable window that makes the delay happen but faster flip-flops help in making the process faster and reduce the time delay as well.