Graphene and 2D Materials in Electronics

Royole, Samsung and Huawei have all recently launched foldable smartphones, that double as phones and tablets-functioning as a phone when closed and a tablet when unfolded. Other smartphone companies including Oppo, Vivo, Xiaomi and Lenovo, are also bringin foldable models to the market in 2019.

These innovations have been driven by the use of new materials that allow for improvements in flexibility and conductivity. Graphene and 2D Materials are key to the future development of consumer electronic and wearable devices with flexible form factors.

Published March 4 2019 | 125 pages

TABLE OF CONTENTS

1    EXECUTIVE SUMMARY…………………………………………………………. 13

• 1.1     Flexible smartphones……………………………………………………………………………………………………………. 13
• 1.2     The evolution of electronics……………………………………………………………………………………………………. 14
  • 1.2.1       The wearables revolution………………………………………………………………………………………………. 15
  • 1.2.2       Flexible, thin, and large-area form factors………………………………………………………………………….. 16
• 1.3     What are flexible and stretchable electronics?…………………………………………………………………………….. 17
  • 1.3.1       From rigid to flexible and stretchable………………………………………………………………………………… 17
  • 1.3.2       Organic and printed electronics……………………………………………………………………………………….. 19
  • 1.3.3       New conductive materials………………………………………………………………………………………………. 20
• 1.4     Growth in flexible and stetchable electronics market…………………………………………………………………….. 22
  • 1.4.1       Recent growth in printable, flexible and stretchable products…………………………………………………. 23
  • 1.4.2       Future growth……………………………………………………………………………………………………………… 23
  • 1.4.3       Nanotechnology as a market driver………………………………………………………………………………….. 24
  • 1.4.4       Growth in remote health monitoring and diagnostics……………………………………………………………. 24
• 1.5     Two-dimensional (2D) materials………………………………………………………………………………………………. 26
• 1.6     Graphene…………………………………………………………………………………………………………………………… 26

2    GRAPHENE ELECTRONICS MARKET ANALYSIS……………………. 27

• 2.1     FLEXIBLE ELECTRONICS, WEARABLES, CONDUCTIVE FILMS AND DISPLAYS…………………………… 28
  • 2.1.1       MARKET DRIVERS AND TRENDS…………………………………………………………………………………. 28
  • 2.1.2       APPLICATIONS………………………………………………………………………………………………………….. 30
    • 2.1.2.1    Transparent electrodes in flexible electronics…………………………………………………………………. 33
    • 2.1.2.2    Electronic paper………………………………………………………………………………………………………. 35
    • 2.1.2.3    Wearable electronics………………………………………………………………………………………………… 35
    • 2.1.2.4    Wearable sensors……………………………………………………………………………………………………. 38
    • 2.1.2.5    Industrial monitoring…………………………………………………………………………………………………. 43
    • 2.1.2.6    Wearable and mobile health monitoring………………………………………………………………………… 44
    • 2.1.2.7    Military………………………………………………………………………………………………………………….. 52
  • 2.1.3       PRODUCT DEVELOPERS…………………………………………………………………………………………….. 52
• 2.2     CONDUCTIVE INKS…………………………………………………………………………………………………………….. 63
  • 2.2.1       MARKET DRIVERS AND TRENDS…………………………………………………………………………………. 64
  • 2.2.2       APPLICATIONS………………………………………………………………………………………………………….. 64
    • 2.2.2.1    RFID…………………………………………………………………………………………………………………….. 67
    • 2.2.2.2    Smart labels…………………………………………………………………………………………………………… 68
    • 2.2.2.3    Smart clothing…………………………………………………………………………………………………………. 69
    • 2.2.2.4    Printable sensors…………………………………………………………………………………………………….. 69
    • 2.2.2.5    Printed batteries………………………………………………………………………………………………………. 69
    • 2.2.2.6    Printable antennas…………………………………………………………………………………………………… 71
  • 2.2.3       PRODUCT DEVELOPERS…………………………………………………………………………………………….. 72
• 2.3     TRANSISTORS AND INTEGRATED CIRCUITS…………………………………………………………………………. 78
  • 2.3.1       MARKET DRIVERS AND TRENDS…………………………………………………………………………………. 79
  • 2.3.2       APPLICATIONS………………………………………………………………………………………………………….. 80
    • 2.3.2.1    Integrated circuits…………………………………………………………………………………………………….. 80
    • 2.3.2.2    Transistors…………………………………………………………………………………………………………….. 81
    • 2.3.2.3    Graphene Radio Frequency (RF) circuits………………………………………………………………………. 81
    • 2.3.2.4    Graphene spintronics……………………………………………………………………………………………….. 82
  • 2.3.3       PRODUCT DEVELOPERS…………………………………………………………………………………………….. 83
• 2.4     MEMORY DEVICES…………………………………………………………………………………………………………….. 88
  • 2.4.1       MARKET DRIVERS AND TRENDS…………………………………………………………………………………. 88
  • 2.4.2       APPLICATIONS………………………………………………………………………………………………………….. 89
  • 2.4.3       PRODUCT DEVELOPERS…………………………………………………………………………………………….. 92

3    OTHER 2-D MATERIALS IN ELECTRONICS…………………………….. 95

• 3.1     Beyond moore’s law……………………………………………………………………………………………………………… 96
• 3.2     Batteries…………………………………………………………………………………………………………………………….. 97
• 3.3     PHOSPHORENE…………………………………………………………………………………………………………………. 97
  • 3.3.1       Properties………………………………………………………………………………………………………………….. 97
  • 3.3.2       Applications in electronics……………………………………………………………………………………………… 99
• 3.4     GRAPHITIC CARBON NITRIDE (g-C3N4)……………………………………………………………………………….. 100
  • 3.4.1       Properties…………………………………………………………………………………………………………………. 100
  • 3.4.2       Synthesis…………………………………………………………………………………………………………………. 101
  • 3.4.3       C₂N…………………………………………………………………………………………………………………………. 101
  • 3.4.4       Applications in electronics…………………………………………………………………………………………….. 101
• 3.5     GERMANENE……………………………………………………………………………………………………………………. 102
  • 3.5.1       Properties…………………………………………………………………………………………………………………. 102
  • 3.5.2       Applications in electronics…………………………………………………………………………………………….. 102
• 3.6     GRAPHDIYNE…………………………………………………………………………………………………………………… 103
  • 3.6.1       Properties…………………………………………………………………………………………………………………. 103
  • 3.6.2       Applications in electronics…………………………………………………………………………………………….. 103
• 3.7     GRAPHANE……………………………………………………………………………………………………………………… 104
  • 3.7.1       Properties…………………………………………………………………………………………………………………. 104
  • 3.7.2       Applications in electronics…………………………………………………………………………………………….. 104
• 3.8     HEXAGONAL BORON-NITRIDE……………………………………………………………………………………………. 104
  • 3.8.1       Properties…………………………………………………………………………………………………………………. 105
  • 3.8.2       Applications in electronics…………………………………………………………………………………………….. 105
• 3.9     MOLYBDENUM DISULFIDE (MoS₂)……………………………………………………………………………………….. 106
  • 3.9.1       Properties…………………………………………………………………………………………………………………. 106
  • 3.9.2       Applications in electronics…………………………………………………………………………………………….. 107
• 3.10        RHENIUM DISULFIDE (ReS2) AND DISELENIDE (ReSe2)…………………………………………………….. 108
  • 3.10.1     Properties…………………………………………………………………………………………………………………. 108
  • 3.10.2     Applications in electronics…………………………………………………………………………………………….. 108
• 3.11        SILICENE…………………………………………………………………………………………………………………….. 109
  • 3.11.1     Properties…………………………………………………………………………………………………………………. 109
  • 3.11.2     Applications in electronics…………………………………………………………………………………………….. 110
• 3.12        STANENE/TINENE…………………………………………………………………………………………………………. 110
  • 3.12.1     Properties…………………………………………………………………………………………………………………. 111
  • 3.12.2     Applications in eectronics…………………………………………………………………………………………….. 112
• 3.13        TUNGSTEN DISELENIDE……………………………………………………………………………………………….. 112
  • 3.13.1     Properties…………………………………………………………………………………………………………………. 112
  • 3.13.2     Applications in electronics…………………………………………………………………………………………….. 112
• 3.14        ANTIMONENE………………………………………………………………………………………………………………. 113
  • 3.14.1     Properties…………………………………………………………………………………………………………………. 113
  • 3.14.2     Applications………………………………………………………………………………………………………………. 113
• 3.15        INDIUM SELENIDE………………………………………………………………………………………………………… 113
  • 3.15.1     Properties…………………………………………………………………………………………………………………. 113
  • 3.15.2     Applications in electronics…………………………………………………………………………………………….. 114

4    REFERENCES…………………………………………………………………….. 115

TABLES

• Table 1. Foldable/bendable smartphone product launches 2019…………………………………………………………………. 14
• Table 2: Evolution of wearable devices, 2011-2019………………………………………………………………………………….. 16
• Table 3: Advanced materials for printable, flexible and stretchable sensors and Electronics-Advantages and disadvantages……………………………………………………………………………………………………………………………. 20
• Table 4: Sheet resistance (RS) and transparency (T) values for transparent conductive oxides and alternative materials for transparent conductive electrodes (TCE)……………………………………………………………………………………… 21
• Table 5: Markets for wearable devices and applications…………………………………………………………………………….. 23
• Table 6: Market drivers for use of graphene in flexible electronics and conductive films……………………………………. 28
• Table 7: Applications and benefits of graphene in flexible electronics and conductive films……………………………….. 31
• Table 8: Comparison of ITO replacements……………………………………………………………………………………………… 32
• Table 9: Wearable electronics devices and stage of development……………………………………………………………….. 36
• Table 10: Graphene properties relevant to application in sensors………………………………………………………………… 41
• Table 11: Applications in flexible and stretchable health monitors, by advanced materials type and benefits thereof.. 46
• Table 12: Market drivers for use of graphene in conductive inks………………………………………………………………….. 64
• Table 13: Comparative properties of conductive inks………………………………………………………………………………… 65
• Table 14: Printable electronics products………………………………………………………………………………………………… 66
• Table 15: Opportunities for advanced materials in printed electronics…………………………………………………………… 68
• Table 16: Applications in flexible and stretchable batteries, by nanomaterials type and benefits thereof……………….. 70
• Table 17: Market drivers for use of graphene in transistors, integrated circuits and other components…………………. 79
• Table 18: Comparative properties of silicon and graphene transistors…………………………………………………………… 81
• Table 19: Applications and benefits of graphene in transistors, integrated circuits and other components…………….. 82
• Table 20: Market drivers for use of graphene in memory devices………………………………………………………………… 88
• Table 24: 2D materials types……………………………………………………………………………………………………………….. 95
• Table 25: Electronic and mechanical properties of monolayer phosphorene, graphene and MoS₂……………………….. 98

FIGURES

• Figure 1. Huawei Mate X foldable smartphone………………………………………………………………………………………… 13
• Figure 2: Evolution of electronics………………………………………………………………………………………………………….. 15
• Figure 3: Wove Band…………………………………………………………………………………………………………………………. 18
• Figure 4: Wearable graphene medical sensor…………………………………………………………………………………………. 19
• Figure 5: Applications timeline for organic and printed electronics……………………………………………………………….. 20
• Figure 6: Mimo Baby Monitor………………………………………………………………………………………………………………. 25
• Figure 7: Wearable health monitor incorporating graphene photodetectors……………………………………………………. 25
• Figure 8: Moxi flexible film developed for smartphone application………………………………………………………………… 30
• Figure 9: Flexible graphene touch screen………………………………………………………………………………………………. 31
• Figure 10: Galapad Settler smartphone…………………………………………………………………………………………………. 31
• Figure 11: Flexible organic light emitting diode (OLED) using graphene electrode…………………………………………… 32
• Figure 12: Graphene electrochromic devices. Top left: Exploded-view illustration of the graphene electrochromic device. The device is formed by attaching two graphene-coated PVC substrates face-to-face and filling the gap with a liquid ionic electrolyte………………………………………………………………………………………………………………………….. 34
• Figure 13: Flexible mobile phones with graphene transparent conductive film………………………………………………… 35
• Figure 14: Foldable graphene E-paper………………………………………………………………………………………………….. 35
• Figure 15: Covestro wearables…………………………………………………………………………………………………………….. 37
• Figure 16: Softceptor sensor……………………………………………………………………………………………………………….. 39
• Figure 17: BeBop Media Arm Controller…………………………………………………………………………………………………. 40
• Figure 18: LG Innotek flexible textile pressure sensor……………………………………………………………………………….. 40
• Figure 19: C2Sense flexible sensor………………………………………………………………………………………………………. 41
• Figure 20: Wearable gas sensor…………………………………………………………………………………………………………… 42
• Figure 21: BeBop Sensors Marcel Modular Data Gloves……………………………………………………………………………. 43
• Figure 22: BeBop Sensors Smart Helmet Sensor System………………………………………………………………………….. 44
• Figure 23: Connected human body……………………………………………………………………………………………………….. 44
• Figure 24: Flexible, lightweight temperature sensor………………………………………………………………………………….. 45
• Figure 25: Graphene-based E-skin patch……………………………………………………………………………………………….. 46
• Figure 26: Smart e-skin system comprising health-monitoring sensors, displays, and ultra flexible PLEDs……………. 47
• Figure 27: Graphene medical patch………………………………………………………………………………………………………. 48
• Figure 28: TempTraQ wearable wireless thermometer………………………………………………………………………………. 49
• Figure 29: Mimo baby monitor……………………………………………………………………………………………………………… 49
• Figure 30: Nanowire skin hydration patch………………………………………………………………………………………………. 50
• Figure 31: Wearable sweat sensor……………………………………………………………………………………………………….. 50
• Figure 32: GraphWear wearable sweat sensor………………………………………………………………………………………… 51
• Figure 33: Torso and Extremities Protection (TEP) system…………………………………………………………………………. 52
• Figure 34: The GF1 Graphene Watch……………………………………………………………………………………………………. 63
• Figure 35: BGT Materials graphene ink product………………………………………………………………………………………. 66
• Figure 36: Printed graphene conductive ink……………………………………………………………………………………………. 67
• Figure 37: Flexible RFID tag……………………………………………………………………………………………………………….. 67
• Figure 38: Textiles covered in conductive graphene ink…………………………………………………………………………….. 69
• Figure 39: Enfucell Printed Battery……………………………………………………………………………………………………….. 71
• Figure 40: Graphene printed antenna……………………………………………………………………………………………………. 71
• Figure 41: Printed antennas for aircraft………………………………………………………………………………………………….. 72
• Figure 42: Graphene IC in wafer tester………………………………………………………………………………………………….. 80
• Figure 43: A monolayer WS2-based flexible transistor array……………………………………………………………………….. 81
• Figure 44: Schematic cross-section of a graphene based transistor (GBT, left) and a graphene field-effect transistor (GFET, right)……………………………………………………………………………………………………………………………… 82
• Figure 45: Graphene oxide-based RRAm device on a flexible substrate……………………………………………………….. 89
• Figure 46: Layered structure of tantalum oxide, multilayer graphene and platinum used for resistive random access memory (RRAM)………………………………………………………………………………………………………………………… 90
• Figure 47: A schematic diagram for the mechanism of the resistive switching in metal/GO/Pt…………………………….. 91
• Figure 48: Carbon nanotubes NRAM chip………………………………………………………………………………………………. 91
• Figure 49: Stretchable SWCNT memory and logic devices for wearable electronics………………………………………… 92
• Figure 53: Schematic of 2-D materials…………………………………………………………………………………………………… 96
• Figure 54: Black phosphorus structure…………………………………………………………………………………………………… 97
• Figure 55: Black Phosphorus crystal……………………………………………………………………………………………………… 98
• Figure 56: Bottom gated flexible few-layer phosphorene transistors with the hydrophobic dielectric encapsulation… 100
• Figure 57: Graphitic carbon nitride………………………………………………………………………………………………………. 101
• Figure 58: Structural difference between graphene and C2N-h2D crystal: (a) graphene; (b) C2N-h2D crystal. Credit: Ulsan National Institute of Science and Technology………………………………………………………………………….. 101
• Figure 59: Schematic of germanene……………………………………………………………………………………………………. 102
• Figure 60: Graphdiyne structure…………………………………………………………………………………………………………. 103
• Figure 61: Schematic of Graphane crystal…………………………………………………………………………………………….. 104
• Figure 62: Structure of hexagonal boron nitride……………………………………………………………………………………… 105
• Figure 63: Structure of 2D molybdenum disulfide……………………………………………………………………………………. 106
• Figure 64: SEM image of MoS₂………………………………………………………………………………………………………….. 107
• Figure 65: Atomic force microscopy image of a representative MoS2 thin-film transistor………………………………….. 108
• Figure 66: Schematic of a monolayer of rhenium disulfide………………………………………………………………………… 108
• Figure 67: Silicene structure………………………………………………………………………………………………………………. 109
• Figure 68: Monolayer silicene on a silver (111) substrate…………………………………………………………………………. 110
• Figure 69: Silicene transistor……………………………………………………………………………………………………………… 110
• Figure 70: Crystal structure for stanene……………………………………………………………………………………………….. 111
• Figure 71: Atomic structure model for the 2D stanene on Bi2Te3(111)………………………………………………………… 111
• Figure 72: Schematic of tungsten diselenide…………………………………………………………………………………………. 112
• Figure 73: Schematic of Indium Selenide (InSe)…………………………………………………………………………………….. 114