Write-erase and read paper memory transistor

Abstract

We report the architecture and the performances of a memory based on a single field-effect transistor built on paper able to write-erase and read. The device is composed of natural multilayer cellulose fibers that simultaneously act as structural support and gate dielectric; active and passive multicomponent amorphous oxides that work as the channel and gate electrode layers, respectively, complemented by the use of patterned metal layers as source/drain electrodes. The devices exhibit a large counterclockwise hysteresis associated with the memory effect, with a turn-on voltage shift between 1 and −14.5 V, on/off ratio and saturation mobilities of about 10 4 and 40 cm 2 V −1 s −1 , respectively, and estimated charge retention times above 14 000 h. © 2008 American Institute of Physics. ͓DOI: 10.1063/1.3030873͔Nowadays the microelectronics industry is demanding for inexpensive, lightweight, and disposable memory devices. This has been pushing research toward the use of low cost materials and devices whose structures are easily fabricated at low temperatures and with low energy consumption. This demand is mainly fulfilled by organic devices and several attempts have been made to use them as memories: to write and read information, 1 for random access memory circuits for storing and retrieving information, 2 and nonvolatile memories. 3 Nevertheless, all these organic memory devices still suffer from a low carrier mobility ͑below 3-7 cm 2 V −1 s −1 ͒ that limits the device switching time and exhibit low charge retention times ͑4500 s͒ 3 that restricts their field of applications. Up to now, paper has been mainly used either as substrate in organic thin-film transistors ͑TFTs͒ 4 , logic circuits, 5 and electrochromic displays, 6 or in thin-film flexible Li batteries. 7 Here we show the possibility to use multilayer mechanically compact natural cellulose fibers ͑paper͒ simultaneously as structural support and dielectric in n-type memory field-effect transistors able to writeerase and read ͑WERM-FETs͒. The channel and gate electrode layers are respectively based on active and passive multicomponent amorphous oxides such as gallium indium zinc oxide ͑GIZO͒ 8 and indium zinc oxide ͑IZO͒. 9 The WERM-FETs were fabricated at room temperature in a three step process described elsewhere, 10 using paper from Renova 11 composed by long pine fibers mixed with polyester fibers, embedded in a matrix of an ionic resin and adhesive glue to give the need mechanical stiffness. The paper surface was treated with an amylaceous solution to make it hydrophobic. On one side of the paper sheet ͑55 m thick͒, a 40 nm thick amorphous GIZO ͑Ga 2 O 3 -In 2 O 3 -ZnO; 1:2:1 mol %͒ deposited by rf magnetron sputtering coats the surface of the fibers ͑acting as the channel layer͒. This was followed by e-beam assisted evaporation of the Al or Au source/drain thick electrodes that connect all fibers over the edges of the patterned channel region, using shadow masks with a width-to-length ratio of 2165/ 216 m, see Fig. 1͑a͒. After, the paper is turned u...

Material characteristics and applications of transparent amorphous oxide semiconductors

“…As indicated above, flexible OLEDs [9,23] and flexible ring oscillators have been reported [20]. Flexible substrate materials have been extended to the fabrication of 'paper electronics'; AOS TFTs [24] and memory [25] fabricated on cellulose using a-IGZO and a-IZO TFTs, respectively, have been reported.…”

Paper‐Based, Capacitive Touch Pads

“…To demonstrate the functionality of all the keys in SI Video 3, we set the password to "0, 1,2,3,4,5,6,7,8,9". When disarmed, the electronics lit the green LED, and opening the box did not trigger the alarm.…”

“…Developments in paper-based electronics include ring oscillators with organic electronics [1] , transistors [2][3][4] , methods for patterning conductive traces [5][6][7] , speakers [8] , super capacitors [9] , batteries [10] , MEMS [11] , and solar cells [12] . Each of these developments focuses on a single technological advance that would enable new types of consumer products.…”

Printed unmanned aerial vehicles using paper-based electroactive polymer actuators and organic ion gel transistors

“…IPMC actuators can be driven by low voltages below 5 V; however, they typically require large driving currents that exceed the largest currents achievable by printed organic thin film transistors (OTFTs). However, the on-current of OTFTs can be increased by orders of magnitude if an ion gel is employed as the gate dielectric [35][36][37][38] . Because of the lower operation speed of mechanical components compared with electrical circuits, the limited high-frequency performance of ion gel transistors is of little concern here.…”