Layout techniques for phase correct and gridded wiring

The article describes a brief history of the development of microprocessors. The emphasis is mainly on the technology of manufacturing, silicon wafer fabrication and microstructuring operations, as well as assembly and fabrication equipment. In conclusion, the application of microprocessors is discussed with examples.

digital integrated electronics

The paper presents an area and speed efficient CMOS layout design of shift register on 180 nanometer (nm) technology. The proposed shift register is designed using Serial In Serial Out (SISO) and Serial In Parallel Out (SIPO) techniques. Shift registers are commonly used in large number of sequential circuits and processors for temporary storage of data. The area and speed of developed layout designs are improved by optimized placement and routing for layout. The schematic and layout of both designs are simulated and analyzed using Cadence software. It can be observed from simulated results that the delay of SISO register is 0.97 ns and the delay of SIPO register is 0.71 ns. The SISO register shows 78.6% improvement in delay and SIPO register shows 27.46 % improvement in delay. The silicon area consumption of SISO register is 140.6 nm x 129.49 nm and SIPO register is 130.98 nm x 85.91 nm to provide cost effective solution for Very Large Scale Integration (VLSI) applications.

The methodology for implementing the design of silicon micromachined devices in a standard CMOS foundry process is discussed, and a modified Magic technology file is introduced. The modified technology file is used to design silicon micromachined devices and circtuts that are fabricated using a standard CMOS foundry through the MOSIS service. An additional maskless etch in EDP is required to realize the micromechanical structures once chips are delivered. The modified technology file implements a layer that we call "open" that consists of a combination of active area, contact cut, via, and glass opening. This open area exposes the silicon surface for the anisotropic etch procedure that creates suspended bridges of polysilicon or metal encapsulated in Si02. Results from fabricated chips are included.

Lecture Notes in Electrical Engineering, 2011

The use of general descriptive names, registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use.

2020

The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use.

IEEE Transactions on Components, Packaging, and Manufacturing Technology: Part C, 1997

Interest in integrating the design and manufacture of semiconductor devices has been growing over the past decade. Often referred to as design for manufacture (DFM), integrated product development seeks to conceive and refine design alternatives that make the best use of manufacturing capabilities, in terms of the various materials, processes, tools, equipment, and facilities available realize the design. While there is a large and growing literature on DFM generally, comparatively little of the published work addresses design for semiconductor manufacturing (DFSM) specifically, or the unique technologies and special circumstances of the semiconductor industry.

1999

1. Introduction: As digital Integrated Circuits (ICs) are driven at higher and higher clock frequencies, the need for a better clock net routing scheme has become essential. For complex ASICs (or VLSI), circuit designers ensure proper timing by carefully planning and implementing the distribution of clocks throughout the circuit. This part of the design process is critical because poor clock distribution can cause a circuit to malfunction, especially because of problems caused by skew and latency. To minimize skew and latency, circuit designers create clock trees that balance delays and loads in the clock buffers. There is less room for error when the clock period becomes small, so great care must be taken to deliver the clock pulse to all points.

Most digital designers will never be confronted with the details of the manufacturing process that lies at the core of the semiconductor revolution. Yet, some insight in the steps that lead to an operational silicon chip comes in quite handy in understanding the physical constraints that are imposed on a designer of an integrated circuit, as well as the impact of the fabrication process on issues such as cost. In this chapter, we briefly describe the steps and techniques used in a modern integrated circuit manufacturing process. It is not our aim to present a detailed description of the fabrication technology, which easily deserves a complete course [Plummer00]. Rather we aim at presenting the general outline of the flow and the interaction between the various steps. We learn that a set of optical masks forms the central interface between the intrinsics of the manufacturing process and the design that the user wants to see transferred to the silicon fabric. The masks define the patterns that, when transcribed onto the different layers of the semiconductor material, form the elements of the electronic devices and the interconnecting wires. As such, these patterns have to adhere to some constraints in terms of minimum width and separation if the resulting circuit is to be fully functional. This collection of constraints is called the design rule set, and acts as the contract between the circuit designer and the process engineer. If the designer adheres to these rules, he gets a guarantee that his circuit will be manufacturable. An overview of the common design rules, encountered in modern CMOS processes, will be given. Finally, an overview is given of the IC packaging options. The package forms the interface between the circuit implemented on the silicon die and the outside world, and as such has a major impact on the performance, reliability, longevity, and cost of the integrated circuit. 2.2 Manufacturing CMOS Integrated Circuits A simplified cross section of a typical CMOS inverter is shown in Figure 2.1. The CMOS process requires that both n-channel (NMOS) and p-channel (PMOS) transistors be built in the same silicon material. To accommodate both types of devices, special regions called wells must be created in which the semiconductor material is opposite to the type of the channel. A PMOS transistor has to be created in either an n-type substrate or an n-well, while an NMOS device resides in either a p-type substrate or a p-well.

1997