Integrated Circuits are used in most people\u2019s lives in the modern societies. An important branch of research and technology is focused on Integrated Circuit (IC) design, fabrication, and their efficient applications; moreover most of these activities are about commercial productions with applications in ambient environment. However the ICs play very important role in very advance research fields, as Astronomy or High Energy Physics experiments, with absolutely extreme environments which require very interdisciplinary
research orientations and innovative solutions. For example, the Fast TracKer (FTK) electronic system, which is an important part of triggering system in ATLAS experiment at European Organization for Nuclear Research (CERN), in every second of experiment selects 200 interesting events among 40 millions of total events due to collision of accelerated protons. The FTK function is based on ICs which work as Content Addressable Memory (CAM). A CAM compares the income data with stored data and gives the addresses of matching data as an output. The amount of calculation in FTK system is out of capacity of commercial ICs even in very advanced technologies, therefore the development of innovative ICs is required. The high power consumption due to huge amount of calculation was an important limitation which is overcome by an innovative architecture of CAM in this dissertation.
The environment of ICs application in astrophysics and High Energy Physics experiments is different from commercial ICs environment because of high amount of radiation. This fact started to get seriously attention after the first \u201cTelstar I\u201d satellite failure because of electronic damages due to radiation effects in space, and opened a new field of research mostly about radiation hard electronics.
The multidisciplinary research in radiation hard electronic field is about radiation effects on semiconductors and ICs, deep understanding about the radiation in the extreme environments, finding alternative solutions to increase the radiation tolerance of electronic components, and development of new simulation method and test techniques.
Chapter 2 of this dissertation is about the radiation effects on Silicon and ICs. Moreover, In this chapter, the terminologies of radiation effects on ICs are explained. In chapter 3, the space and high energy physics experiments environments, which are two main branches of radiation hard electronics research, are studied.
The radiation tolerance in on-chip circuits is achieving by two kinds of methodology: Radiation Hardening By Process (RHBP) and Radiation Hardening By Design (RHBD). RHBP is achieved by changing the conventional fabrication process of commercial ICs. RHBP is very expensive so it is out of budget for academic research, and in most cases it is exclusive for military application, with very restricted rules which make the access of non-military organizations impossible.
RHBD with conventional process is the approach of radiation hard IC design in this dissertation. RHBD at hardware level can be achieved in different ways:
\u2022 System level RHBD: radiation hardening at system level is achieved by algorithms which are able to extract correct data using redundant information.
\u2022Architecture level RHBD: some hardware architectures are able to prevent of lost data or mitigate the radiation effects on stored data without interfacing of software. Error Correction Code (ECC) circuits
and Dual Interlocked storage CEll (DICE) architecture are two examples of RHBD at architecture level.
\u2022 Circuit level RHBD: at circuit level, some structures are avoided or significantly reduced. For example, feedback loops with high gain are very sensitive to radiation effects.
\u2022 Layout level RHBD: there are also different solutions in layout design level to increase the radiation tolerance of circuits. Specific shapes of transistor design, optimization of the physical distance between redundant data and efficient polarization of substrate are some techniques commonly used to increase significantly the radiation tolerance of ICs.
An innovative radiation hard Static Random Access Memory (SRAM), designed in three versions, is presented in chapter 4. The radiation hardening is achieved by RHBD approach simultaneously at architecture, circuit and layout levels. Complementary Metal-Oxide-Semiconductor (CMOS) 65 nm is the technology of design and the prototype chip is fabricated at Taiwan Semiconductor Manufacturing Company (TSMC).
Chapter 5 is about the development of simulation models that can help to predict the radiation effect in the behavior of SRAM block.
The setup system developed to characterize the radiation hard SRAM prototype chip is presented in Chapter 5. The setup system gives the possibility of testing the prototype exposed under radiation in a vacuum chamberand regular laboratory environment.
Chapter 6 is about the contribution of this dissertation on FTK project and the conclusion of all research activities is shown in the final part of this dissertation.
The research activities of this dissertation in supported by Italian National Institute for Nuclear Physics (INFN) as part of CHIPIX65 project and RD53 collaboration at CERN
