KR20140050993A - Zn compound semiconductor and thin film transistor comprising the same - Google Patents
Zn compound semiconductor and thin film transistor comprising the same Download PDFInfo
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- KR20140050993A KR20140050993A KR1020120117503A KR20120117503A KR20140050993A KR 20140050993 A KR20140050993 A KR 20140050993A KR 1020120117503 A KR1020120117503 A KR 1020120117503A KR 20120117503 A KR20120117503 A KR 20120117503A KR 20140050993 A KR20140050993 A KR 20140050993A
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- Prior art keywords
- compound semiconductor
- thin film
- film transistor
- channel
- phase
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- 239000004065 semiconductor Substances 0.000 title claims abstract description 79
- 150000001875 compounds Chemical class 0.000 title claims abstract description 77
- 239000010409 thin film Substances 0.000 title abstract description 31
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 19
- 238000000034 method Methods 0.000 claims description 19
- 239000000463 material Substances 0.000 claims description 11
- 229910052757 nitrogen Inorganic materials 0.000 claims description 8
- 229910052684 Cerium Inorganic materials 0.000 claims description 3
- 229910052693 Europium Inorganic materials 0.000 claims description 3
- 229910052688 Gadolinium Inorganic materials 0.000 claims description 3
- 229910052765 Lutetium Inorganic materials 0.000 claims description 3
- 229910052779 Neodymium Inorganic materials 0.000 claims description 3
- 229910052777 Praseodymium Inorganic materials 0.000 claims description 3
- 229910052772 Samarium Inorganic materials 0.000 claims description 3
- 229910052771 Terbium Inorganic materials 0.000 claims description 3
- 229910052769 Ytterbium Inorganic materials 0.000 claims description 3
- 229910021480 group 4 element Inorganic materials 0.000 claims description 2
- 239000012212 insulator Substances 0.000 claims description 2
- 229910052746 lanthanum Inorganic materials 0.000 claims description 2
- 239000000460 chlorine Substances 0.000 description 26
- 239000000758 substrate Substances 0.000 description 26
- 229910052751 metal Inorganic materials 0.000 description 10
- 239000002184 metal Substances 0.000 description 10
- 229910021417 amorphous silicon Inorganic materials 0.000 description 9
- 239000000203 mixture Substances 0.000 description 8
- 239000004020 conductor Substances 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 6
- 229910004298 SiO 2 Inorganic materials 0.000 description 4
- 239000008186 active pharmaceutical agent Substances 0.000 description 4
- 229910045601 alloy Inorganic materials 0.000 description 4
- 239000000956 alloy Substances 0.000 description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
- 238000000151 deposition Methods 0.000 description 4
- 230000008021 deposition Effects 0.000 description 4
- 229910044991 metal oxide Inorganic materials 0.000 description 4
- 150000004706 metal oxides Chemical class 0.000 description 4
- 150000004767 nitrides Chemical class 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- 229910021420 polycrystalline silicon Inorganic materials 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 238000012546 transfer Methods 0.000 description 4
- 229910052782 aluminium Inorganic materials 0.000 description 3
- 238000005229 chemical vapour deposition Methods 0.000 description 3
- 229910001873 dinitrogen Inorganic materials 0.000 description 3
- 229910001882 dioxygen Inorganic materials 0.000 description 3
- 239000011521 glass Substances 0.000 description 3
- 239000011810 insulating material Substances 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- 229910052719 titanium Inorganic materials 0.000 description 3
- 238000000231 atomic layer deposition Methods 0.000 description 2
- 229910052801 chlorine Inorganic materials 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000004973 liquid crystal related substance Substances 0.000 description 2
- 229910001092 metal group alloy Inorganic materials 0.000 description 2
- 239000011368 organic material Substances 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 238000000059 patterning Methods 0.000 description 2
- 238000005240 physical vapour deposition Methods 0.000 description 2
- 229910052697 platinum Inorganic materials 0.000 description 2
- 238000004151 rapid thermal annealing Methods 0.000 description 2
- 238000004544 sputter deposition Methods 0.000 description 2
- 229910052721 tungsten Inorganic materials 0.000 description 2
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- 229910000584 Cl alloy Inorganic materials 0.000 description 1
- 229910052692 Dysprosium Inorganic materials 0.000 description 1
- 229910052691 Erbium Inorganic materials 0.000 description 1
- 229910052689 Holmium Inorganic materials 0.000 description 1
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 229910052775 Thulium Inorganic materials 0.000 description 1
- 229910052787 antimony Inorganic materials 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 229910052733 gallium Inorganic materials 0.000 description 1
- 229910021478 group 5 element Inorganic materials 0.000 description 1
- 229910052735 hafnium Inorganic materials 0.000 description 1
- VBJZVLUMGGDVMO-UHFFFAOYSA-N hafnium atom Chemical compound [Hf] VBJZVLUMGGDVMO-UHFFFAOYSA-N 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000002513 implantation Methods 0.000 description 1
- 229910052738 indium Inorganic materials 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002159 nanocrystal Substances 0.000 description 1
- 229910052758 niobium Inorganic materials 0.000 description 1
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 238000009832 plasma treatment Methods 0.000 description 1
- 238000005546 reactive sputtering Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 229910052727 yttrium Inorganic materials 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
- H01L29/12—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
- H01L29/24—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed including, apart from doping materials or other impurities, only semiconductor materials not provided for in groups H01L29/16, H01L29/18, H01L29/20, H01L29/22
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
- H01L29/68—Types of semiconductor device ; Multistep manufacturing processes therefor controllable by only the electric current supplied, or only the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched
- H01L29/76—Unipolar devices, e.g. field effect transistors
- H01L29/772—Field effect transistors
- H01L29/78—Field effect transistors with field effect produced by an insulated gate
- H01L29/786—Thin film transistors, i.e. transistors with a channel being at least partly a thin film
- H01L29/78696—Thin film transistors, i.e. transistors with a channel being at least partly a thin film characterised by the structure of the channel, e.g. multichannel, transverse or longitudinal shape, length or width, doping structure, or the overlap or alignment between the channel and the gate, the source or the drain, or the contacting structure of the channel
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- Engineering & Computer Science (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- Ceramic Engineering (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Computer Hardware Design (AREA)
- Thin Film Transistor (AREA)
Abstract
Zn compound semiconductor and a thin film transistor including the same. The disclosed Zn compound semiconductor can control the carrier concentration in the Zn compound semiconductor to an appropriate level by adding Cl.
Description
The disclosed embodiments relate to a compound semiconductor and a thin film transistor including the compound semiconductor. More particularly, the present invention relates to a semiconductor material to which a new substance is added to a Zn compound and a thin film transistor including the same.
BACKGROUND ART [0002] Thin film transistors are currently used in various fields. In particular, they are used as switching and driving devices in a display field, and are used as selection switches of a cross-point type memory device.
Currently, liquid crystal display (LCD) is the main axis for TV panels, and organic light emitting displays are being studied for application to TV. The development of display technology for TVs is developing in a way to meet the demands of the market. The market requires large-sized TV or DID (Digital Information Display), low price, high definition (video expression power, high resolution, brightness, contrast ratio, color reproduction). In order to meet such requirements, there is a need for a thin film transistor to be applied as a switching and driving device of a display having excellent performance, along with enlargement of a substrate such as glass.
An amorphous silicon thin film transistor (a-Si TFT) is used as a driving and switching element of a display. This is the most widely used device which can be formed uniformly on a large substrate over 2m * 2m at low cost. However, due to the trend toward larger and higher-resolution displays, high performance is required for device performance, and it is believed that the conventional a-Si TFT having a mobility of 0.5 cm 2 / Vs will reach the limit. Therefore, there is a need for high-performance TFTs and manufacturing techniques with higher mobility than a-Si TFTs.
Polycrystalline silicon thin film transistor (poly-Si TFT), which has much higher performance than a-Si TFT, has a high mobility of several tens to several hundreds cm 2 / Vs, and thus can be applied to a high- . In addition, the problem of deterioration of the device characteristics is very small as compared with the a-Si TFT. However, in order to fabricate a poly-Si TFT, a complicated process is required compared to an a-Si TFT, and the additional cost is also increased. Therefore, p-Si TFT is suitable for high definition display and products such as OLED, but its cost is inferior to that of conventional a-Si TFT, so its application is limited. In the case of p-Si TFTs, manufacturing processes using large-sized substrates larger than 1 m have not been realized so far due to technical problems such as limitations of manufacturing equipment and unevenness in uniformity. Thus, application to TV products is difficult.
Accordingly, there is a demand for a new TFT technology having both advantages of a-Si TFT and advantages of poly-Si TFT. Research has been actively conducted on this, and a representative example thereof is a Zn compound semiconductor device. Zn compound semiconductors are Zn oxide semiconductors based on Zn-based multi-cation compounds and Zn oxynitride semiconductor devices doped with multi-anion compositions.
One aspect of the present invention relates to a Zn compound semiconductor including Cl.
Another aspect of the present invention relates to a thin film transistor using a Zn compound semiconductor including Cl in a channel region.
In the embodiment of the present invention,
In the Zn compound semiconductor,
The Zn compound semiconductor is composed of Zn and nitrogen,
The Zn compound semiconductor can provide a Zn compound semiconductor further containing Cl.
The Zn compound semiconductor may include Zn oxynitride to which Cl is added.
The Zn compound semiconductor may be formed of a material containing nitrogen and Cl in Zn.
The Zn compound semiconductor may include an amorphous phase.
The Zn compound semiconductor may include a nanocrystalline phase.
The Zn compound semiconductor may have a mixed phase structure of an amorphous phase and a crystalline phase.
The Zn compound semiconductor may be a Group I element, a Group II element, a Group III element, a Group IV element or an Ln series element (La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, , Yb, Lu).
Further, in the embodiment of the present invention,
A gate electrode;
A channel formed at a position corresponding to the gate electrode and formed by adding Cl to a Zn compound semiconductor containing Zn and nitrogen;
A gate insulator formed between the gate electrode and the channel; And
And a Zn compound semiconductor having a source and a drain formed in contact with both sides of the channel, respectively.
According to the embodiment of the present invention, by adding Cl to the Zn compound semiconductor, the characteristics of the high mobility device can be ensured by controlling the carrier concentration in the Zn compound semiconductor to an appropriate level.
1 is a view illustrating a bottom structure thin film transistor including a Zn compound semiconductor according to an embodiment of the present invention.
FIG. 2 is a view showing a top-type thin film transistor including a Zn compound semiconductor according to an embodiment of the present invention.
3A to 3E are views illustrating a method of manufacturing a thin film transistor including a Zn compound semiconductor according to an embodiment of the present invention.
FIGS. 4A and 4B show transfer curves of a thin film transistor using a thin film not doped with Cl and a thin film doped with Cl in a Zn compound semiconductor as a channel, and the gate voltage (V GS ) -drain current I DS ).
Hereinafter, a Zn compound semiconductor and a thin film transistor including the Zn compound semiconductor according to an embodiment of the present invention will be described in detail with reference to the drawings. It should be borne in mind that the thickness and width of each layer shown in the figures are exaggerated for clarity.
1 is a cross-sectional view illustrating a structure of a thin film transistor including a Zn compound semiconductor according to an embodiment of the present invention. 1 shows a bottom gate type thin film transistor.
1, a thin film transistor including a Zn compound semiconductor according to an embodiment of the present invention includes a
The
2 is a cross-sectional view illustrating a structure of a thin film transistor including a Zn compound semiconductor according to an embodiment of the present invention. 2 shows a top gate type thin film transistor.
2, a
The Zn compound semiconductor according to an embodiment of the present invention may be a substance in which Cl is further added to Zn oxynitride or a substance containing nitrogen and Cl in Zn, . The Zn compound semiconductor according to an embodiment of the present invention may be formed in a mixed phase including both crystalline, amorphous, crystalline, and amorphous phases. In addition, the thin film transistor including the Zn compound semiconductor according to the embodiment of the present invention may be formed of a material containing Zn-oxynitride with Cl added thereto or a material containing Zn, 22).
Hereinafter, materials constituting each layer of the Zn compound semiconductor and the thin film transistor including the Zn compound semiconductor according to the embodiment of the present invention shown in FIGS. 1 and 2 will be described.
The
The
The
The
The
The Zn compound semiconductor according to the embodiment of the present invention can be used as a driving transistor used in a flat panel display, a liquid crystal display (LCD), or an OLED (Organic Light Emitting Diodes), a transistor constituting a peripheral circuit of a memory element, Channel material.
Hereinafter, a method of manufacturing a thin film transistor including a Zn compound semiconductor according to an embodiment of the present invention will be described with reference to FIGS. 3A to 3E. Here, a method of manufacturing the bottom gate type thin film transistor shown in FIG. 1 will be described.
Referring to FIG. 3A, a
Referring to FIG. 3B, the
3D, after forming a Zn compound layer in which Cl is added by a process such as PVD (Physical Vapor Deposition), CVD (Chemical Vapor Deposition) or ALD (atomic layer deposition) on the
Referring to FIG. 3E, a metal, a metal alloy, a conductive metal oxide, or a conductive metal nitride, which is a conductive material, is formed on the
FIGS. 4A and 4B are transfer curves of a thin film transistor using a Zn compound semiconductor as a channel, and are graphs showing changes in gate voltage (V GS ) -drain current (I DS ). Here, FIG. 4A shows a case of using a Zn compound semiconductor not doped with Cl as a channel, and FIG. 4B shows a transfer cuff when a Zn compound semiconductor doped with Cl is used as a channel. Here, the change in the drain current (I DS ) relative to the gate voltage (V GS ) was measured for each of the specimens 4 (PT1, PT2, PT3, PT4)
Referring to FIGS. 4A and 4B, in the case of FIG. 4B, the ON current is about 10 -2 to 10 -3 A, the OFF current is 10 -10 A or less, and the ON / 10 7 or more, indicating high on / off current ratio and low off current, and satisfies the characteristics as a transistor. On the other hand, in the case of FIG. 4A, the off current value is high, so that the on / off current ratio is lower than that of FIG. 4B. That is, when Cl is added to the Zn chemical semiconductor, the off current value is relatively decreased and the on / off current ratio is increased.
In addition, mobility and swing value tended to decrease when Cl was gradually added to the Zn compound semiconductor. When the composition of Cl is increased in the Zn compound semiconductor, the carrier concentration in the Zn compound semiconductor can be controlled to an appropriate level and the swing value of the transfer curve can be reduced. In the Zn compound semiconductor, the composition ratio of Cl to materials other than Zn can be selectively controlled.
It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Various electronic devices such as transistors for constitution can be manufactured. The composition ratio of the Zn compound semiconductor and the I DS -V GS graph according to the embodiment of the present invention can be changed depending on the type of the target used, the target applied voltage at the time of deposition, the deposition equipment, the deposition pressure, the oxygen partial pressure condition, . Also, even if the deposited thin film composition is the same, the characteristics of the thin film can be changed according to the deposition conditions. For example, the composition ratio of the Zn compound semiconductor can be controlled by controlling the partial pressure of oxygen or nitrogen gas supplied in the sputtering process.
The oxide thin film transistor according to an embodiment of the present invention can be used as a bottom gate type or a top gate type. As a result, the scope of the present invention is not to be determined by the described embodiments but should be determined by the technical idea described in the claims.
10, 20 ...
14, 28 ...
19, 22 ...
18b, 24b ... drain
Claims (12)
The Zn compound semiconductor is composed of Zn and nitrogen,
Wherein the Zn compound semiconductor further comprises Cl.
Wherein the Zn compound semiconductor is Zn compound semiconductor containing Zn oxynitride to which Cl is added.
The Zn compound semiconductor is formed of a material containing nitrogen and Cl in Zn.
Wherein the Zn compound semiconductor includes an amorphous phase.
The Zn compound semiconductor includes a nanocrystalline phase.
The Zn compound semiconductor has a mixed phase structure of an amorphous phase and a crystalline phase.
The Zn compound semiconductor may be a Group I element, a Group II element, a Group III element, a Group IV element or an Ln series element (La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, , Yb, Lu).
A channel formed at a position corresponding to the gate electrode and formed by adding Cl to a Zn compound semiconductor containing Zn and nitrogen;
A gate insulator formed between the gate electrode and the channel; And
And a Zn compound semiconductor having a source and a drain formed in contact with both sides of the channel.
Wherein the Zn compound semiconductor includes a Zn compound semiconductor that is Zn oxynitride to which Cl is added.
Wherein the Zn compound semiconductor comprises a Zn compound semiconductor including an amorphous phase.
Wherein the Zn compound semiconductor includes a Zn compound semiconductor including a nanocrystalline phase.
Wherein the Zn compound semiconductor includes a Zn compound semiconductor having a mixed phase structure of an amorphous phase and a crystalline phase.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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KR1020120117503A KR20140050993A (en) | 2012-10-22 | 2012-10-22 | Zn compound semiconductor and thin film transistor comprising the same |
Applications Claiming Priority (1)
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KR1020120117503A KR20140050993A (en) | 2012-10-22 | 2012-10-22 | Zn compound semiconductor and thin film transistor comprising the same |
Publications (1)
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KR20140050993A true KR20140050993A (en) | 2014-04-30 |
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KR1020120117503A KR20140050993A (en) | 2012-10-22 | 2012-10-22 | Zn compound semiconductor and thin film transistor comprising the same |
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2012
- 2012-10-22 KR KR1020120117503A patent/KR20140050993A/en not_active Application Discontinuation
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