DE102012107959A1 - Electronic components, useful for passivating metal oxide layer functional layer, include functional layer that comprises metal oxides and is coated with protective layer comprising epoxide compound and/or rearrangement product - Google Patents

Abstract

Electronic components (1), preferably semiconductor components comprise a functional layer (2) that comprises metal oxides and is coated with a protective layer (3) comprising an epoxide compound (I) and/or a rearrangement product (II). Electronic components (1), preferably semiconductor components comprise a functional layer (2) that comprises metal oxides and is coated with a protective layer (3) comprising an epoxide compound of formula (I) and/or a rearrangement product of formula (II). R1-R4 : X or C nX 2 n + 1; X : H, F, Cl, Br or I, where X contains at least 20%, preferably at least 50%, 55%, 60%, 65% , 70%, 75%, 80%, 85%, 90%, 95% or 100% of F (preferred), Cl, Br or I; n : 1-10, provided that not all X are simultaneously H, and when R1 and R3 are each H then R2 is C(O)R5 to form a ketone group of formula (R4-C(=O)-CH 2-C(=O)-R5) (III); and either R4a, R5 : cyclic, acyclic, linear or branched, aliphatic or aryl (optionally substituted); or R4a+R5 : aliphatic or aryl, optionally substituted mono- or polycyclic ring system. An independent claim is included for producing the electronic components. [Image].

Description

The invention relates to electronic components, in particular semiconductor components and a method for their production.

For electronic components, e.g. in photovoltaic cells / modules or in the control electronics of modern flat panel displays, metal oxides are used as transparent conductors or as high mobility semiconductors. Metal oxide functional layers are currently produced by means of expensive growth techniques (MOCVD, sputter deposition), or stabilized by subsequent tempering or additional protective layers, so that they are suitable for applications.

Metal oxides are sensitive to environmental conditions. For example, oxygen escapes from the functional layer in vacuum or adsorbs moisture under normal atmospheric conditions. Both change the electronic properties (doping, mobility, etc.) of the metal oxides, which is a significant problem in applications. This is especially true when using inexpensive methods used for large area coatings, as here metal oxide functional layers with many grain boundaries, i. with many defects and with a large surface-to-volume ratio.

The object of the present invention is to provide a possibility to protect or stabilize metal oxide functional layers of electronic components better than before.

The object is solved by the subjects of the independent claims. Advantageous embodiments are specified in the subclaims.

und/oder ein Umlagerungsprodukt davon gemäß derallgemeinen Formel (Ib)

umfasst, oder aus der Verbindung (Ia) und/oder dem Umlagerungsprodukt (Ib) besteht,
wobei R¹, R², R³ und R⁴, jeweils unabhängig, X oder C_nX_2n+1 ist,
X, für jeden und innerhalb der Reste R¹, R², R³ und R⁴ unabhängig, H, F, Cl, Br oder I ist,
n, für jeden der Reste R¹, R², R³ und R⁴ unabhängig, 1, 2, 3, 4, 5, 6, 7, 8, 9 oder 10 ist,
mit der Maßgabe, dass nicht alle X gleichzeitig H sind. In a first aspect, the present invention provides an electronic component, in particular a semiconductor component, which comprises a functional layer comprising metal oxides or metal oxides, the functional layer being coated with a protective layer comprising a compound of the general formula (Ia)

and / or a rearrangement product thereof according to the general formula (Ib)

comprises, or consists of the compound (Ia) and / or the rearrangement product (Ib),
wherein R ¹ , R ² , R ³ and R ⁴ , each independently, is X or C _n X _{2n + 1} ,
X is, independently for each and within the radicals R ¹ , R ² , R ³ and R ⁴ , H, F, Cl, Br or I,
n, independently for each of R ¹ , R ² , R ³ and R ⁴ , is 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10,
with the proviso that not all X are H at the same time.

Rearrangements to the keto compound (Ib) can in particular take place only if at least one of the radicals R is a fluorine atom. It has surprisingly been found that the surface of a metal oxide functional layer, including possible defects, is passivated by the coating with a compound according to formula Ia or with a rearrangement product thereof. The electronic properties stabilize, since the escape of oxygen, the absorption of moisture and similar undesirable processes on the surface of the functional layer are hindered or prevented by the applied molecules. The invention also makes use of the fact that the compound or its rearrangement product has pronounced water-repellent properties.

An "electronic component" is understood here as the smallest basic component of an electrical circuit considered as a unit. An electronic component may optionally be composed of several components. Examples of electronic components are resistors, Potentiometers, sensors, microelectromechanical systems (MEMS), capacitors, coils, tubes, loudspeakers, relays, inductors, transformers, rechargeable batteries, fuel cells, diodes, photodiodes, light emitting diodes (LEDs, OLEDs), solar cells, photoelements, phototransistors, optocouplers, Thermal generators, transistors, integrated circuits (ICs), SMDs (Surface Mounted Devices), fuses, surge arresters and thyristors.

A "semiconductor device" is understood to mean electronic components which are manufactured from semiconductor materials or comprise these. Semiconductor materials are solids that can function both as conductors and as nonconductors with regard to their electrical conductivity. The specific resistance ρ of semiconductors lies between that of nonconductors and conductors. Examples of such materials are silicon, germanium, α-selenium, zinc oxide, tetracene, gallium arsenide (GaAs), indium phosphide (InP), CdS, PbS, PbSe, etc. Examples of semiconductor devices are diodes, transistors, thyristors, triacs, triacs, light emitting diodes ( LED, OLEDs), photodiodes, phototransistors, CCD sensors, solar cells, thermocouples, Peltier elements etc.

As used herein, when referring to a "rearrangement product" of a compound is meant a compound of the same molecular formula formed by regrouping the atoms of the compound, cleaving and reforming one or more C-C bonds. In particular, here are meant compounds which by opening the oxirane ring of the compounds of formulas Ia, Ib or Ic to form a carbonyl group involving a C atom of Oxiranrings and simultaneous displacement of a residue located at this C atom to the other carbon atom of the Oxirane rings arise.

The feature according to which X, independently for each and within the radicals R ¹ , R ² , R ³ and R ⁴ , is H, F, Cl, Br or I, means that X in each of its occurrences independently of any other X on the same radical or another radical from the list consisting of H, F, Cl, Br or I can be selected. The radicals R ^1, R ^2, R ³ and R ⁴ may thus have mutually identical or different X or identical and / or different combination of H, F, Cl, Br or I. For example, the radicals R ¹ and R ⁴ each be F (fluorine), while R ² is Cl (chlorine) and R ³ is C ₂ X ₅ (n = 2), where in R ^{3 is} again various combinations of H, F, Cl , Br or I are possible, for example C ₂ F ₅ , CCl ₂ -CF ₂ H or CBrH-CClFH.

The feature that n is independent of each of R ¹ , R ² , R ³ and R ⁴ means that n need not be the same for all R ¹ , R ² , R ³ and R ⁴ , but for each Rest can be different. For example, n may be R ¹ = 1, R ² = 2, R ³ = 2 and R ⁴ = 3. Of course, n can be the same for all residues.

When it is said that the protective layer comprises a compound of the formula Ia, Ib or Ic, or a rearrangement product thereof, this means that the protective layer contains the corresponding compound or optionally also a mixture of corresponding compounds. The proportion of the compound (s) of the formula Ia, Ib or Ic or of the rearrangement product (s) is preferably at least 5% by weight, at least 10% by weight, at least 15% by weight or at least 20% by weight .-%, more preferably at least 25 wt .-%, 30 wt .-%, 35 wt .-%, 45 wt .-% or 50 wt .-%, and particularly preferably at least 55 wt .-%, 60 wt. %, 65 wt%, 70 wt%, 75 wt%, 80 wt%, 90 wt%, 95 wt%, 96 wt%, 97 wt% %, 98 wt%, 99 wt% or 100 wt%.

The term "metal oxide functional layer" is understood to mean layers having defined electrical and / or optical properties, which consist of metal oxides or contain metal oxides.

Chemical vapor deposition (CVD) is understood here to mean coating processes known to the person skilled in the art, in which a solid component is deposited on the heated surface of a substrate on the basis of a chemical reaction from the gas phase. By "physical vapor deposition" (PVD) is meant here a coating process known to the person skilled in the art, in which a starting material is removed by means of physical processes, e.g. under vacuum or vacuum, is transferred into the gas phase and passed to the substrate to be coated, where it condenses to form the target layer.

X is preferably at least 20%, preferably at least 25%, 30%, 35%, 40% or 45%, particularly preferably at least 50%, 55%, 60%, 65%, 70%, of the compound used for the coating. , 75%, 80%, 85%, 90%, 95% or 100% F, Cl, Br or I, preferably F.

mit n = 1, 2, 3, 4, 5, 6, 7, 8, 9 oder 10, besonders bevorzugt 1, 2, 3, 4 oder 5, und/oder ein Umlagerungsprodukt davon umfasst, oder aus der Verbindung (Ic) oder dem Umlagerungsprodukt besteht. Besonders bevorzugt umfasst die Schutzschicht Hexafluorpropylenoxid (HFPO, 2,2,3-Trifluor-3-(trifluormethyl)oxiran, C₃OF₆) oder besteht aus Hexafluorpropylenoxid. It is particularly preferred in the case of the electronic component according to the invention if the protective layer comprises a compound according to the general formula (Ic)

with n = 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, more preferably 1, 2, 3, 4 or 5, and / or a rearrangement product thereof, or of the compound (Ic) or the rearrangement product. Particularly preferably, the protective layer comprises hexafluoropropylene oxide (HFPO, 2,2,3-trifluoro-3- (trifluoromethyl) oxirane, C ₃ OF ₆ ) or consists of hexafluoropropylene oxide.

und/oder ein Umlagerungsprodukt davon gemäß der allgemeinen Formel (Ib)

umfasst, oder aus der Verbindung (Ia) und/oder dem Umlagerungsprodukt besteht,
wobei R¹, R², R³ und R⁴, jeweils unabhängig, X oder C_nX_2n+1 ist,
X, für jeden und innerhalb der Reste R¹, R², R³ und R⁴ unabhängig, H, F, Cl, Br oder I ist,
n, für jeden der Reste R¹, R², R³ und R⁴ unabhängig, 1, 2, 3, 4, 5, 6, 7, 8, 9 oder 10 ist,
mit der Maßgabe, dass nicht alle X gleichzeitig H sind. In a second aspect, the present invention also relates to a method for producing an electronic component, in particular a semiconductor component, according to the first aspect of the invention. The functional layer is coated in the process according to the invention with a protective layer comprising a compound of the general formula (Ia)

and / or a rearrangement product thereof according to the general formula (Ib)

comprises, or consists of the compound (Ia) and / or the rearrangement product,
wherein R ¹ , R ² , R ³ and R ⁴ , each independently, is X or C _n X _{2n + 1} ,
X is, independently for each and within the radicals R ¹ , R ² , R ³ and R ⁴ , H, F, Cl, Br or I,
n, independently for each of R ¹ , R ² , R ³ and R ⁴ , is 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10,
with the proviso that not all X are H at the same time.

Preferably, X is at least 20%, preferably at least 25%, 30%, 35%, 40% or 45%, more preferably at least 50%, 55%, 60%, 65%, 70%, 75%, 80%. , 85%, 90%, 95% or 100% F, Cl, Br or I, preferably F.

mit n = 1, 2, 3, 4, 5, 6, 7, 8, 9 oder 10, besonders bevorzugt 1, 2, 3, 4 oder 5, und/oder ein Umlagerungsprodukt davon umfasst, oder aus der Verbindung (Ic) und/oder dem Umlagerungsprodukt besteht. The functional layer is preferably coated with a protective layer which comprises a compound according to the general formula (Ic)

with n = 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, more preferably 1, 2, 3, 4 or 5, and / or a rearrangement product thereof, or of the compound (Ic) and / or the rearrangement product.

Particularly preferably, the functional layer is coated with a protective layer which comprises hexafluoropropylene oxide or consists of hexafluoropropylene oxide.

The functional layer is preferably coated with the protective layer by means of physical or chemical vapor deposition. Without wishing to be bound by theory, it is assumed that, in the process according to the invention, compound molecules according to the formulas Ia, Ib and / or Ic are adsorbed on the surface of a metal oxide functional layer and form a protective monolayer there.

The invention is explained in more detail below purely for illustrative purposes with reference to an embodiment. It shows

1 Schematic representation of an embodiment of an electronic component according to the invention, here a transistor.

2 Electrical characterization of an untreated and an HFPO-treated ZnO transistor in air. 2A : Untreated ZnO transistor, impact of negative bias stress (nbs) at V _GS = -20V / V _DS = 5V for 4000 s; 2 B : Untreated ZnO transistor, impact of positive bias stress (pbs) at V _GS = -20V / V _DS = 5V for 4000 s; 2C : HFPO-treated ZnO transistor, impact of negative bias stress (nbs) at V _GS = -20V / V _DS = 5V for 4000 s; HFPO-treated ZnO transistor, effect of positive bias stress (pbs) at V _GS = -20V / V _DS = 5V for 4000 s. V _GS = "gate-source" voltage, V _DS = "drain-source" voltage, I _D = drain current.

1 schematically shows a section through a transistor, which is designed according to the present invention. Illustrated by way of example is a transistor in bottom-gate-bottom-contact configuration. On a heavily doped silicon wafer 6 which serves as a substrate and as a gate electrode is a gate dielectric 5 made of SiO ₂ . Above is a metal oxide functional layer deposited by means of spray pyrolysis 4 , here a semiconductor layer of zinc oxide. With the reference number 3 are source and drain electrodes made of gold with ITO ("indium tin oxide", indium tin oxide) referred to as adhesion promoter. On the surface of the metal oxide functional layer 4 is a protective layer 2 made of HFPO.

• 1. Reinigung des Si-Wafers und der strukturierten Source- und Drain-Kontakte mit Isopropanol (IPA) und Aceton im Ultraschallbad und Ozon.
• 2. Abscheiden des ZnO-Films aus einer wässrigen Zinkacetat-Precursor-Lösung bei 360°C mittels Spraypyrolyse. Tempern der Probe für 20 Minuten bei 500°C.
• 3. Überführen der Probe in einen Rundkolben und anschließende Evakuierung des Kolbens mit Hilfe einer Wasserstrahlpumpe.
• 4. Einleitung von HFPO in den Kolben und Einwirkenlassen über 2 Stunden.
• 5. Abpumpen von verbliebenem HFPO-Gas, Fluten der Apparatur mit Stickstoff und Entnahme der Probe.
• 7. Nach dem Beschichtungsprozess erfolgt erneut eine elektrische Charakterisierung der Probe.
• 8. Außerdem wird die Veränderung in der Oberflächenenergie mittels Kontaktwinkelmessung untersucht.

To investigate the properties of the transistor according to 1 a corresponding sample was prepared as follows:

• 1. Cleaning the Si wafer and the structured source and drain contacts with isopropanol (IPA) and acetone in an ultrasonic bath and ozone.
• 2. deposition of the ZnO film from an aqueous zinc acetate precursor solution at 360 ° C by spray pyrolysis. Anneal the sample for 20 minutes at 500 ° C.
• 3. Transfer the sample to a round bottom flask and then evacuate the flask using a water jet pump.
• 4. Introduction of HFPO into the flask and exposure over 2 hours.
• 5. Pumping off remaining HFPO gas, flooding the apparatus with nitrogen and taking out the sample.
• 7. After the coating process, an electrical characterization of the sample takes place again.
• 8. In addition, the change in the surface energy is examined by means of contact angle measurement.

Between step 2 and 3 and after the coating process, an electrical characterization of the sample was carried out. In addition, the change in surface energy was examined by contact angle measurement.

In electrical characterization, the effects of negative and positive bias stress (nbs, pbs) at V _GS = -20V / V _DS = 5V were studied for 4000s. 2 ). The significantly lower displacements of the measured curves relative to the initial situation (= 0 s) for the coated samples ( 2C , D) showed a significantly increased stability of the components compared to the uncoated samples ( 2A , B) for the same power.

The contact angle measurements gave values of 77 ° for the untreated surface compared to 87 ° for the treated surface. The fluorinated surface was thus substantially more hydrophobic than the untreated ZnO surface.

Claims (9)

Electronic component, in particular semiconductor component, wherein the electronic component ( 1 ) a functional layer comprising metal oxides or metal oxides ( 2 ), characterized in that the functional layer ( 2 ) is coated with a protective layer ( 3 ) which is a compound of general formula (Ia)

and / or a rearrangement product thereof according to the general formula (Ib)

or consisting of the compound (Ia) and / or the rearrangement product, wherein R ¹ , R ² , R ³ and R ⁴ , each independently, is X or C _n X _{2n + 1} , X, for each and within the radicals R ¹ , R ² , R ³ and R ^{4 are} independently H, F, Cl, Br or I, n, independently for each of R ¹ , R ² , R ³ and R ⁴ , 1, 2, 3, 4 , 5, 6, 7, 8, 9 or 10, with the proviso that not all X are simultaneously H; Electronic component according to Claim 1, characterized in that X contains at least 20%, preferably at least 25%, 30%, 35%, 40% or 45%, particularly preferably at least 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% or 100% F, Cl, Br or I, preferably F, is. Electronic component according to claim 2, characterized in that the protective layer ( 3 ) a compound according to the general formula (Ic)

with n = 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, and / or a rearrangement product thereof, or consists of the compound (Ic) or the rearrangement product. Electronic component according to claim 3, characterized in that the protective layer ( 3 ) Hexafluoropropylene oxide or consists of hexafluoropropylene oxide. Method for producing an electronic component, in particular a semiconductor component, wherein the electronic component comprises a functional layer comprising metal oxides or metal oxides, characterized in that the functional layer is coated with a protective layer comprising a compound of the general formula (Ia)

and / or a rearrangement product thereof according to the general formula (Ib)

comprises, or from the compound (Ia) and / or the rearrangement product (Ib), wherein R ¹ , R ² , R ³ and R ⁴ , each independently, X or C _n X _{2n + 1} , X, for each and R ¹ , R ² , R ³ and R ⁴ independently of one another, H, F, Cl, Br or I, n, for each of the radicals R ¹ , R ² , R ³ and R ⁴ independently, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, with the proviso that not all X are simultaneously H; A method according to claim 5, characterized in that X is at least 20%, preferably at least 25%, 30%, 35%, 40% or 45%, more preferably at least 50%, 55%, 60%, 65%, 70th %, 75%, 80%, 85%, 90%, 95% or 100% F, Cl, Br or I, preferably F, is. A method according to claim 6, characterized in that the functional layer is coated with a protective layer comprising a compound according to the general formula (Ic)

with n = 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 and / or a rearrangement product thereof, or consists of the compound (Ic) and / or the rearrangement product. A method according to claim 7, characterized in that the functional layer is coated with a protective layer which comprises hexafluoropropylene oxide or consists of hexafluoropropylene oxide. Method according to one of claims 5 to 8, characterized in that the functional layer is coated by means of physical or chemical vapor deposition with the protective layer.

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