Complementary Type Ferroelectric Memory Transistor Circuits with P‐ and N‐Channel MoTe₂

Abstract

Ferroelectric nonvolatile memory (FeNVM) field effect transistors (FETs) are reported using p‐channel MoTe2 and P(VDF‐TrFE) ferroelectric polymer, and furthermore a complementary type memory cell is demonstrated coupling p‐ and n‐channel MoTe2 FETs. A top‐gate p‐FET with P(VDF‐TrFE) and a bottom‐gate n‐FET with Al2O3 dielectric are integrated as one cell. Such a complementary type cell is more desirable research path in respect of power consumption but rare to find in 2D‐based memory reports. Among many 2D semiconductors MoTe2 is selected, because p‐type MoTe2‐based FeNVM is not reported yet, and also because it is relatively easy to obtain both p‐ and n‐channel from the homogeneous MoTe2. The integrated device also operates as a complementary metal oxide semiconductor inverter in a small voltage range from 0 to ≈2.5 V, but primarily works as a FeNVM circuit when p‐channel with top P(VDF‐TrFE) is biased with high voltages over the coercive electric field (Ec) of the polymer. The bottom gate n‐channel transistor operates as a switching device in the FeNVM cell, allowing voltage output signals during device operations. It is concluded that the complementary type FeNVM cell is practical and novel enough to report as a first time demonstration based on 2D MoTe2.

2D semiconductors for specific electronic applications: from device to system

“…The large surface-to-volume ratio enables 2D semiconductors highly sensitive to interfacial environments, which greatly enhances the response to external factors such as ferroelectric polarization 99 . The 2D ferroelectric transistors employ organic polymers P(VDF-TrFE) [100][101][102] or inorganic high-κ oxides 103 as their ferroelectric gate dielectric. The most compelling features of these ferroelectric non-volatile memories are their simple device structure, faster access speeds, high endurance and low 108 .…”

Recent Advances in Electrical Doping of 2D Semiconductor Materials: Methods, Analyses, and Applications

“…By simply coating or depositing a film that provides a doping effect, the electrical properties of the TMDs, such as effective mobility, threshold voltage, and subthreshold swing, can be adjusted. This approach enables forming a heterostructure of the doping film and the TMD, in which the electrical or optical characteristics of the TMDs can be enhanced by (i) charge transfer from the dopant molecules to TMDs [ 62 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 , 91 , 92 ] or (ii) dipole effects of the dopant molecules of the doping film [ 4 , 5 , 6 , 7 , 93 , 94 , 95 ]. The energy band structure of MoS 2 could be controlled through molecular doping from the deposited tetrathiafulvalene and dimethyl-phenylenediamine molecules as donors and tetracyanoethylene (TCNE) and tetracyanoquinodimethane (TCNQ) as acceptors ( Figure 6 a,b) [ 72 , 88 ].…”

“…Higher photoresponsivity and temporal photoresponse performance could be achieved by the surface charge transfer doping. Another application is to build complementary circuits by selective doping of TMDs [ 73 , 74 , 80 , 81 , 94 ]. Pristine TMD devices suffer from ambipolar characteristics, normally-on operation due to V TH shift, and contact resistance, which limit implementation to complementary circuits.…”

Self-Assembled Monolayers: Versatile Uses in Electronic Devices from Gate Dielectrics, Dopants, and Biosensing Linkers

“…In the second section, the effects of SAMs acting as dopants on the device's properties are introduced. In the last decade, promising semiconductor materials, including transition metal dichalcogenides (TMDs) [56][57][58][59][60], oxides [61][62][63][64][65], and polymers [66][67][68][69][70], have emerged as next-generation semiconductors. However, the conventional doping techniques (i.e., ion implantation) used in silicon-based fabrications degrade and damage these semiconductors; thus, there is a need for the development of alternative methods to control the electrical properties of the semiconductors.…”