CN208570615U

CN208570615U - The more channel thin-film transistors of germanium nanometer film flexible metal type

Info

Publication number: CN208570615U
Application number: CN201821009348.7U
Authority: CN
Inventors: 秦国轩; 裴智慧
Original assignee: Tianjin University
Current assignee: Tianjin University
Priority date: 2018-06-28
Filing date: 2018-06-28
Publication date: 2019-03-01
Anticipated expiration: 2028-06-28

Abstract

The utility model belongs to flexible electronic device field, to reduce production cost, light transmission is more excellent, so that the flexible device may in the application offer of large scale integrated circuit and photoelectric device, the utility model, the more channel thin-film transistors of germanium nanometer film flexible metal type, structure is as follows: being followed successively by metallic film above flexible polyethylene terephtalate, hafnium dioxide gate dielectric layer, it is germanium nanometer film layer above hafnium dioxide gate dielectric layer, it is that N-type leaks doped region and its upper metal drain electrode in the middle part of germanium nanometer film layer, N-type is leaked on the outside of doped region for undoped with area, N-type source dopant region there are two being laid on the outside of the undoped area, it draws to form corresponding two metal sources through conducting wire in two N-type source dopant regions；It is zinc oxide gate dielectric layer above the undoped area；Metal gates are penetrated the through-hole of hafnium dioxide gate dielectric layer and conductive metallic film forms Ohmic contact.The utility model is mainly used in flexible electronic device and manufactures and designs occasion.

Description

The more channel thin-film transistors of germanium nanometer film flexible metal type

Technical field

The utility model belongs to flexible device field, and in particular to a kind of more ditches of flexible metal grid based on germanium nanometer film The structure of road thin film transistor (TFT) designs and preparation.

Background technique

Flexible electronic be by organic and inorganic material electronics element manufacturing on flexible, Drawability plastics or thin metal matrix plate New electronic science and technology, all there is extensive use in fields such as information, the energy, medical treatment, national defence.Such as print RFID (radio frequency identification Label), electronics surface mount, Organic Light Emitting Diode OLED, flexible electronic displays etc..With traditional IC (integrated circuit) skill Art is the same, and the main drive of flexible electronic technology development is manufacturing process and equipment.With lower on the substrate of more large format Cost produce the smaller flexible electronic device of characteristic size and become the key of manufacture.The utility model is based on using one kind The novel process of germanium nanometer film preparation, using magnetron sputtering conductive film and dual dielectric layer grid, after photoetching ion etching with And the technology of HF (hydrofluoric acid) wet etching, by the germanium nanometer film stripping on GOI (germanium on insulator) and be transferred to flexibility can It is bent on PET substrate, then forms channel structure transistor more than one by way of photoetching layer by layer and etching, be expected in the future In wearable electronic, extensive flexible integration circuit etc. obtains extensive use.

Summary of the invention

In order to overcome the deficiencies of the prior art, the utility model is directed to make using more channel structure extreme enrichment transistors For the use of circuit components.In addition, driving using bottom and top metallic transparent conductive film, production cost, light transmission are reduced Performance is more excellent, so that the flexible device may in the application offer of large scale integrated circuit and photoelectric device.For this purpose, this reality The technical solution adopted is that, the more channel thin-film transistors of germanium nanometer film flexible metal type, structure is as follows: flexible with novel Metallic film, hafnium dioxide gate dielectric layer are followed successively by above polyethylene terephtalate, on hafnium dioxide gate dielectric layer Side is germanium nanometer film layer, is that N-type leaks doped region and its upper metal drain electrode in the middle part of germanium nanometer film layer, N-type is leaked on the outside of doped region For undoped with area, there are two N-type source dopant regions for the undoped area outside laying, and shape is drawn through conducting wire in two N-type source dopant regions At corresponding two metal sources；It is zinc oxide gate dielectric layer above the undoped area；Metal gates are through penetrating titanium dioxide The through-hole of hafnium gate dielectric layer and conductive metallic film form Ohmic contact.

The characteristics of the utility model and beneficial effect are:

Device in the utility model has higher integrated level, there is more broad range of application.In addition, the utility model The transistor device being integrated in plastic supporting base still can satisfy the normal work of device when plastic supporting base bending, can With in intelligent wearable device, artificial skin, biologic medical, photoelectric device etc. are obtained and are more widely applied.

Detailed description of the invention:

Attached drawing 1 is the top view of flexible more channel thin-film transistors, and attached drawing 2 is the sectional view of transistor and attached drawing three is The working principle diagram of utility model.Attached drawing 3 is the working principle diagram of utility model.

Specific embodiment

The purpose of this utility model is that designing and preparing a kind of germanium nanometer of more channel structures based on flexible PET substrate Film transistor, using the low temperature process of magnetron sputtering, designed in relatively simple technique and prepare more channel structures have it is higher Gate driving control ability flexible thin-film transistor, using more channel structure extreme enrichments transistor as circuit elements device The use of part.In addition, driving using bottom and top metallic transparent conductive film, production cost is reduced, light transmission is more It is excellent, so that the flexible device provides possibility in the application of large scale integrated circuit and photoelectric device.

The technical solution of the utility model is to plate metal and hafnium oxide on PET substrate using magnetron sputtering technique Gate dielectric film then forms doped region by the way of being lithographically formed pattern and ion implanting, is carved using photoetching and ion The mode of erosion forms square hole layer, forms germanium nanometer film layer by the way of wet process HF etching, poly- in flexible by transfer Germanium nanometer film is formed on ethylene glycol terephthalate PET substrate, the mode finally by photoetching and magnetron sputtering distinguishes shape At top hafnium oxide gate dielectric layer and source and drain grid metal electrode layer.Complete the preparation of transistor.

The main operational principle of the flexibility bottom gate homogenous medium layer film transistor is by upper and lower three gate electrodes Upper addition bias will form electron inversion floor in source and drain doping area, as the conducting channel of device, device in place of gate oxide Part conducting, then adds bias between source-drain electrode, and device will start to work, by grid voltage control device whether be connected with And between the source and drain of device electric current principle, further, since up and down gate electrode package action make grid have it is stronger for The control ability of channel current, control ability increases more times under same grid voltage, and flexible substrate can reduce traditional silicon substrate The ghost effect of substrate MOS FET (Metal Oxide Semiconductor Field Effect Transistor) transistor, and can be in different bending journeys It works under degree, providing for the large-scale integrated of high-performance flexible circuit and the extensive use of wearable electronic can Energy.

The utility model is further described with specific example with reference to the accompanying drawing.

In attached drawing 1 and attached drawing 2: 1 and 5 be metal source on N-type source dopant region, and 2 and 4 be undoped on germanium film Area, 3 leak metal leakage pole on doped region for N-type, and 6 and 7 be zinc oxide gate dielectric layer, and 8 and 9 be metal source, and 10 be metal Bottom gate thin film, 11 be through-hole, and 12 be hafnium dioxide gate dielectric layer, and 13 be metallic film, and 14 be PET plastic substrate, and 15 be interconnection Line, 16,17 be top gate electrode, and 18 be germanium film, and 19 be metal leakage pole.

Attached drawing 3 is the working principle diagram of utility model, and some regions on germanium material film are doped can shape At doped region, remaining undoped position is exactly undoped with area.Metallized electrode is formed and can be worked on doped region later Transistor.Germanium nanometer film layer can be transferred on PET by transfer techniques, and the top layer of PET is coated with hafnium oxide gate medium Tunic, so being equivalent to for germanium nanometer film layer being transferred on hafnia film, then plating metal forms electrode again.In metal roof After applying certain bias in portion and bottom gate electrode (corresponding to 10,16,17 in figure), pass through the metal of top and bottom Conductive film, the metal layer in top and bottom generate certain voltage, and when the voltage of application is smaller or no-bias, germanium is received Rice film layer (corresponding to 18 in figure) due to not no inversion layer generation, even if adding voltage between source and drain, between source and drain Electric current, device shutdown will not be generated.When voltage is sufficiently large, germanium nanometer thin film layer will with grid oxide layer (corresponding in figure 6,7,12) generate electron inversion layer (corresponding to the dashed region in figure three) at the surface contacted, script crystal is hollow live in caves it is more Germanium nano thin-film up and down two surfaces, will generate electron number be greater than hole number surface inversion regime, this region is referred to as device Channel region be then biased, can generate between source and drain in the source-drain electrode (corresponding to 8,9,19 in figure) of n-type doping Electric current, break-over of device.Device in the utility model has higher integrated level, there is more broad range of application.In addition, this reality It still can satisfy the normal of device when plastic supporting base bending with the novel transistor device being integrated in plastic supporting base Work, can be in intelligent wearable device, and artificial skin, biologic medical, photoelectric device etc. are obtained and be more widely applied.

Specific manufacture craft is as follows:

A, it selects PET flexible material as substrate, puts PET into the beaker for filling acetone soln first, then super It is cleaned 5 minutes in sound wave washer, it then will in ultrasonic cleaner by the PET cleaned with acetone using aqueous isopropanol Acetone cleans up, and obtains more clean substrate.

B, 200nm thickness metal film and 100nm thickness hafnium oxide bottom dielectric grid layer are plated on PET substrate using magnetron sputtering Film.

C, GOI material is selected, is cleaned in ultrasonic cleaner using acetone, acetone is then cleaned using isopropanol Residue dries up GOI.

D, 1813 positive photo glues are coated on the surface GOI, and uses sol evenning machine, setting revolving speed is 4000rpm, rotation time For 30s, photoresist is got rid of uniformly, then carries out being lithographically formed specific doped region using litho machine and the mask plate made Pattern then carries out N-type injection by the way of ion implanting, and parameter is that Implantation Energy is 40kev, dosage 4*10¹⁵cm^-2, It generates source and drain doped region and after rapid thermal annealing 10s, photoresist is removed in acetone soln under the conditions of 750 DEG C of temperature.

E, according to label ready-made on mask plate, by the square hole of spacing 5um arrangement in source and drain doping area and mask plate Layer carries out alignment photoetching, the small aperture layer of square of spacing 5um arrangement is formed after development on GOI, then using ion etching Mode removes the silicon on square aperture.

F, in the HF solution of 3:1, ready-made GOI before being put into, the buried oxide layer after two hours on GOI will be corroded dry Only, subsequent germanium nanometer film layer will fall off, germanium nanometer film layer is adhered to by transfer techniques plated film flexible PET substrate it On, drying.

G, the gluing in the germanium nanometer film being transferred on PET, according in square aperture layer after being got rid of uniformly with sol evenning machine Label carry out alignment photoetching, form the grid of transistor, then by the way of ion etching, respectively by germanium nanometer film and The gate oxide film layer etching plated, forms Ohmic contact with conductive metal layer.

H, after going photoresist then to carry out spin coating to the device on PET, alignment photoetching, shape are carried out according to the label of grid At the pattern of top gate dielectric layer.

I, finally, carrying out magnetron sputtering on the pattern of formation, it is situated between in the hafnium oxide top gate of top grid plating 100nm thickness Matter layer.

J, it is directed at photoetching after going photoresist then to carry out gluing to the flexible device for forming top gate dielectric layer, forms top-gated With the photoengraving pattern of source-drain electrode, the metal top grid and source-drain electrode of 200nm thickness are formed by the way of magnetron sputtering Layer, after removing photoresist, the preparation of device is completed.

Claims

1. a kind of more channel thin-film transistors of germanium nanometer film flexible metal type, characterized in that structure is as follows: poly- pair of flexible It is followed successively by metallic film, hafnium dioxide gate dielectric layer above ethylene terephthalate PET, is above hafnium dioxide gate dielectric layer Germanium nanometer film layer, germanium nanometer film layer middle part are that N-type leaks doped region and its upper metal drain electrode, and it is not that N-type, which is leaked on the outside of doped region, Doped region, there are two N-type source dopant regions for the undoped area outside laying, and two N-type source dopant regions draw to form phase through conducting wire Two metal sources answered；It is zinc oxide gate dielectric layer above the undoped area；Metal gates are penetrated hafnium oxide grid The through-hole of dielectric layer and conductive metallic film form Ohmic contact.