3D NAND memory devices are intrinsically very cost sensitive, implying that their size, and hence logic area must be limited in order to acquire a chip which is able to conquer the competitive market price. Market forecasts of upcoming NAND products predict Input/Output (I/O) speed increase well beyond 2 Gb/s that is the current industry standard. I/O bandwidth strongly correlates with the device technology used for logic and the current state-of-the-art planar devices are predicted to reach their maximum capabilities in the near future. Use of FinFET transistor is expected to substantially enhance I/O area-performance of 3D NAND memory logic, alleviating area restriction severity and providing a foundation for future periphery generations to come.

In this thesis, a 3D NAND compatible I/O able to achieve 8 Gb/s throughput has been developed using simulation of thermally stable Imec in-house developed 14 nm FinFET technology equivalent. To validate throughput quality, industry defined eye diagram standards are used. To determine area savings provided by utilizing FinFET devices, FinFET active transmitter area is benchmarked against 45 nm planar device setup achieving the same 8 Gb/s data rate performance. To ensure an unbiased comparison, two signaling topologies are used - single ended signaling (SES) and differential signaling (DS). To extend analysis, sensitivity of the design against various parameters such as data rate, voltage and temperature is explored.

It is concluded, that active area of FinFET driver is several times lower than that of similar planar transmitter (same power and throughput) for both SES and DS. Additionally, suitable use cases of DS and SES have been evaluated depending on environmental conditions investigated during sensitivity analysis. All in all, this research provides a baseline for planar-to-FinFET scaling in I/O system and guidelines in choosing signaling topology appropriately, depending on system constraints.
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The inverse scattering problem is inherently nonlinear and improperly posed. Relevant study, such as the existence and uniqueness of the solution, the completeness of the far field pattern, etc., involves an abstruse mathematical theory. In our daily life, the inversion techniques play a significant role in areas such as radar, sonar, geophysical exploration, medical imaging and nondestructive testing. This thesis is focused on the qualitative and quantitative reconstruction of shape and medium parameters of scattering objects in electromagnetic inverse scattering theory. The major contributions of this thesis are 1) the proposal of a novel cross-correlated error termand 2) the proposal of the sum-of-normregularized reconstruction algorithm. The significance of the former lies in the fact that the proposed error term fills up a gap hidden in the classical “state error Å data error” cost functional. In the optimization approaches, the data error term tends to recover the unknown properties of the objects directly from the measurement data, while the state error term attempts to ensure that the recovered results satisfy Maxwell’s equations in the field domain. In other words, the solution must behave well in both the measurement domain and the field domain. However, there is still a gap in between because the minor mismatch in the field domain is not monitored in the measurement domain. The proposed crosscorrelated error is a constraint which tends to get the mismatch in the field domain under control in the measurement domain. Therefore, one can say that this novel error term revolutionizes the formulation of the minimization functional of inversion techniques based on optimization theory. The significance of the latter is that the proposed reconstruction scheme enables us to excavate the joint information hidden in the formulation of multiple inverse source problems, without any significant additional computational effort. Although the sum-of-norm regularization is not necessarily the best regularization constraint for some complicated scatterers, it demonstrates at least two points: 1) for an inverse source problem, benefits can be obtained from use of different incident fields; 2) the sum-of-norm regularization brings better resolving ability due to the joint processing of the multiple contrast source vectors. The research results in this thesis are also applicable to the acoustic inverse scattering problems. Application of the qualitative and quantitative reconstruction approaches developed in this thesis to the experimental data in different areas of wave-field inversion would be very interesting as future work. ... Read more