Research On Memory Circuit Based On New Type Carbon-based Field Effect Transistor

At first,in order to investigate the electrical properties of n-i-n type field-effect transistors based on carbon,a quantum model is adopted based on non-equilibrium Green's function(NEGF)and Poisson equation with self-consistent solution.We research the electrical properties of CNTFETs and GNRFETs which are based on the channel engineering technology and the gate engineering technology.Then,choose the device of the optimal performance apply into the circuit,using the SPICE with look-up table based on Verilog-A models to research the electrical properties.Through the research of this subject,it can provide theoretical basis for future carbon-based devices and circuit design.The main work of this paper can be summarized as follows:(1)Firstly,we study the HMG-LDDS-GNRFET and compare with other related structures.The results show that this new structure can reduce the off-state current,thus increasing the switchingcurrent ratio Ion /Ioff,and sub-threshold swing is also reduced.Compare with the device of general structure HMG-LDDS-GNRFET has lower delay time and higher voltage gain.(2)Secondly,we research electrical characteristics of n-i-n HMG-LDDS-CNT-HFET structure and compare with other related structures.We find that this new structure can also reduce the off-state current,and better current ratio Ion/Ioff.It has a higher cutoff frequency and lower gate capacitance,which suppresses the short channel effect.It has a good cut-off frequency and research ralation about voltage gains and channel length.(3)Finally,this paper uses Verilog-A to establish the look-up table(LUT)model on the basis of the transfer characteristics of the devices,and construct the corresponding circuit in SPICE to analyze its electrical characteristics and compare with other circuit.In the circuit level,we mainly explore performance of the device in the inverter circuit and memory circuit.(1)For the inverter constructed by HMG-LDDS-GNRFET,the results show that the inverter constructed by HMG-LDDS-GNRFET has a smaller power consumption delay product(PDP).Secondly,this structure is used in the design of the classic 6T memory circuit,and compared with the memory circuit constructed by C-GNRFET,it is shown that the SNM value of HLGSRAM circuit is larger than that of CGSRAM,and the comprehensive index SPR of HLGSRAM circuit is twice about the CGSRAMcircuit.That is to say,HMG-LDDS-GNRFET has a better stability.A variety of logic circuits are constructed by HMG-LDDS-CNT-HFET,which verify that the logic function of these logic circuits can be realized correctly.The circuit performance is compared with the ordinary structure.Secondly,the HMG-LDDS-CNT-HFET is used in the 6T memory circuit.The results show that the memory circuit constructed by this new structure has lower delay,power consumption,PDP and higher SNM.