GB2619148A - Dielectric materials based on reversed imide-extended bismaleimides - Google Patents

Abstract

Bismaleimide compounds of general formula

Description

Dielectric Materials Based On Reversed Irnide-Extended Bismaleirnides

Field of the invention

The present invention relates to a new class of dielectric polymer material, which is particularly suitable for the manufacturing of electronic: devices The dielectric polymer material is formed by reacting a new type of bisrnaleimide compound and shows an advantageous well-balanced profile of favorable material properties, particularly with regard to the requirements in advanced electronic packaging applications such as e.g. wafer level packaging (NLP) as well as for low-dielectric adhesive applications. The dielectric polymer material of the present invention shows an advantageous well-balanced profile of material properties including: (a) favorable thermomechanical properties such as e.g. high glass transition temperature (Tg), low coefficient of thermal expansion (CTE), high elongation at break and high tensile strength: (b) favorable dielectric properties such as e.g low dielectric constant and low dielectric loss tangent: and (c) good adhesive properties, in particular high adhesive strength on copper and Si02 passivated wafers.

The dielectric polymer material of the present invention is formed by reacting a bismaleimide compound. As bisrnaleimide compounds, certain reversed imide-extended bismaleirnide compounds are described herein.

Such compounds are photostructurable and can be used as starting material for various applications in electronic device manufacturing such as e.g. for the preparation of repassivation layers in packaged electronic devices (including passivation of conductive or semiconducting components in redistribution layer (ROLs) or die attaches), in thin film formulations and/or in adhesive formulations. In addition, said bismale.imide compounds have and excellent film forming capability and are easy to process from conventional solvents to form the dielectric polymer as a spin-on material. -2 -

The bismaleimide compounds of the present invention have an oligomenc structure with an reversed imicie extended repeating unit in the central part of the molecule and maleimide groups at each terminal end of the molecule.

There is further provided a method for forming said dielectric polymer material. Beyond that, the present invention relates to the dielectric polymer material and to an electronic device comprising said polymer material as dielectric material.

The bismaleimide compounds and related dielectric polymer material of the present invention allow a cost-effective and reliable manufacturing of micro--electronic devices where the number of defective devices caused by mechanical deformation (warping) due to undesirable thermomechanical expansion is significantly reduced.

Background of the invention

As solid-state transistors started to replace vacuum-tube technology, it became possible for electronic components, such as resistors, capacitors, and diodes, to be mounted directly by their leads into printed circuit boards of cards; thus establishing a fundamental building block or level of packaging that is still in use. Complex electronic functions often require more individual components than can be interconnected on a single printed circuit card. Multilayer card capability was accompanied by development of three-dimensional packaging of daughter cards onto multilayer mother boards. Integrated circuitry allows many of the discrete circuit elements such as resistors and diodes to be embedded into individual, relatively small components known as integrated circuit chips or dies. In spite of incredible circuit integration, however, more than one packaging level is typically required, in part because of the technology of integrated circuits itself. Integrated circuit chips are quite fragile, with extremely small terminals. First-level packaging achieves the major functions of mechanically protecting, cooling, and providing capability for electrical connections to the delicate integrated circuit. At least one additional packaging level, such as a printed circuit card, is utilized, as some components (high-power resistors, mechanical switches, capacitors) are not readily integrated onto a chip. For very complex applications, such as mainframe computers, a hierarchy of multiple packaging levels is required.

A wide variety of advanced packaging technologies exist to meet the requirements of today's semiconductor industry. The leading advanced packaging technologies wafer-level packaging (WLP), fan-out wafer level packaging (FOWLP), 2.5D interposers, chip-on-chip stacking, package-on-package stacking, embedded IC -all require structuring of thin substrates, redistribution layers and other components like high resolution inter-connects. The end consumer market presents constant push for lower prices and higher functionality on ever smaller and thinner devices. This drives the need for the next generation packaging with finer features and improved reliability at a competitive manufacturing cost.

Wafer-level packaging (WLP) is one of the most promising semiconductor package technologies for the next generation of compact, high performance electronic devices. In general, WLP is the process of packaging an integrated circuit while it is still part of the wafer. This is in contrast to the more conventional method of cutting the wafer into individual circuits and then packaging them. WLP is based on redistribution layers (RDLs), which enable the connection between the die and the solder balls, resulting in improved signal propagation and smaller form factor (see Figure 1). Major application areas of WLP are srnartphones and wearables due to their size constraints. -4 -

With current materials, VA_P processes are limited to medium chip size applications. The reasons for this limitation are the unsuitable thermornechanical properties and the non-optimized processing of these materials Dielectric materials used for next-generation microchip REDL.s should meet certain requirements. In addition to a low dielectric constant, several thermornechanical properties such as e.g. high glass transition temperature (fg), low coefficient of thermal expansion (STE); high elongation at break and high tensile strength play an important role.

An important material class, which meets some of the above-mentioned requirements, are imide-extended maleimide compounds described in various publications in the state of the art: US 2004/0225026 Al and US 2011/0130485 Al relate to thermosetting (adhesive) compositions comprising irnide-extended mono-, bis-or polymaleimide compounds. The imide-extended maleimide compounds are prepared by the condensation of appropriate anhydrides with appropriate diamines to give amine terminated compounds These compounds are then condensed with excess maleic acid anhydride to yield imide-extended rnaleimide compounds. When incorporated into a thermoset composition, the irnide-extended maleimide compounds are said to reduce brittleness and increase toughness in the composition, while not sacrificing thermal stability.

US 2011/0049731 Al and US 2013/0228901 Al relate to materials and methods for stress reduction in semiconductor wafer passivation layers. Described are compositions containing low modulus photoimageable polyirnides for use as passivating layers and devices comprising a semiconductor wafer and a passivating layer made therefrom.

US 2017/0152418 Al relates to maleimide adhesive films which are prepared from thermosetting maleimide resins containing imide-extended mono-, bis-and polymaleimide compounds. The maleimide adhesive films are said to be photostructurable and suitable for the production of electronic equipment; integrated circuits; semiconductor devices, passive devices, solar batteries, solar modules; and/or light emitting diodes However, the ide-extended maleimide compounds described above have an unfavorable solubility in common solvents used in industry arid an unfavorable profile of thermomechanica: properties such as e.g. a low glass transition temperature; a high coefficient of thermal expansion (GTE) after Tg. When material modifications are aiming to reduce the GTE in this material class, the materials get very brittle and cannot be used in VVLP applications.

Another trend in semiconductor industry concerns the demand for materials with low dielectric properties (low dielectric constant, low dielectric loss tangent) in the high frequency region. The frequency of signals increased with increasing speed of signal transmission in printed circuit boards. In addition; the 53 era requires reliable materials with unique properties to meet specific requirements. In general, the adhesive strength for low dielectric materials is usually poor, since the polarity of these ir1sulating films is typically low. New materials that combine low loss dielectric behavior with good adhesive properties are of great interest for the development of various upcoming applications.

WO 2019/141833 Al relates to dielectric polymers with excellent film forming capability, excellent mechanical properties, a low dielectric constant and a low coefficient of thermal expansion. The dielectric polymers are prepared from polymerizable compounds having mesogenic groups and they can be used as dielectric material for the preparation of passivation layers in electronic devices.

Although these materials have many henel9cial properties, some characteristics, such as the glass transition temperature and processability, need to be increased or improved in order to realize the full potential of these materials.

Materials having a low coefficient thermal expansion (GTE) are reported in S. D. Kim eta;., Sci. Adv., 2018, 4: eaau1956, 1-10 describing new poly(amide-mide) materials for transparent and flexible displays with a GTE value of 4 pprn/K. The novel poly(amide-imicie) materials are based on a 4,4'-biphenyldiamine monomer, where two trifluorornethyl groups are introduced at the 2 and 6 positions on one of the aromatic rings. The materials are said to be transparent and stable at high temperatures and to have a low CTE.

However, such materials exhibit poor adhesive strength and, in terms of material properties, they do not meet all requirements for dielectrics being suitable for modern packaging applications, especially for photoirnageable dielectrics.

Object of the,ention It is an object of the present invention to overcome the drawbacks and disadvantages in the prior art and to provide a new class of dielectric polymer material, which shows an advantageous well-balanced profile of favorable material properties, particularly with regard to requirements in advanced electronic packaging applications such as e.g. wafer level packaging (WLP) as well as for low-dielectric adhesive applications.

Hence, it is an object of the present invention to provide a dielectric polymer material, which shows an advantageous well-balanced profile of material properties including: (a) favorable thermornecnanical properties such as e.g. high glass transition temperature (Tg), low coefficient of thermal -7-expansion (GTE), high elongation at break and high tensile strength; (b) favorable dielectric properties such as e.g. low dielectric constant and low dielectric loss tangent; and (c) good adhesive properties, in particular high adhesive strength on copper and Si02 passivated wafers.

It is a further object of the present invention to provide a bismaleimide compound, from which said dielectric polymer material can be obtained It is an object of the present invention that such bismaleimide compounds are photostructurable and can be used as starting material for various applications in electronic device manufacturing such as e.g. for the preparation of repassivation layers in packaged electronic devices (including passivation of conductive or semiconducting components in a redistribution layer (RDL) or die attach), in thin film formulations and/or in adhesive formulations, In addition, said bismaleimide compounds should have excellent film forming capability and be easy to process from conventional solvents.

Beyond that, it is an object of the present invention to provide a method for forming said dielectric polymer material using the bismaleimide compound.

Finally, it is an object of the present invention to provide the dielectric polymer material and an electronic device comprising said polymer as dielectric material.

It is an object of the present invention that the bismaleimide compounds and related dielectric polymer material allow a cost efficient and reliable manufacturing of microelectronic devices, where the number of defective devices caused by mechanical deformation (warping) due to undesirable thermornechanical properties is significantly reduced,

S

Summary of the invention

The present inventors surprisingly found that the above objects are achieved by a dielectric polymer material, which is formed from a new type of bismaleimide compounds. The dielectric polymer material shows an advantageous well-balanced profile of material properties including: (a) favorable thermomechanical properties such as e.g. high glass transition temperature (Tg), low coefficient of thermal expansion (GTE), high elongation at break and high tensile strength; (b) favorable dielectric properties such as e.g. low dielectric constant and low dielectric loss tangent; and (c) good adhesive properties, in particular high adhesive strength on copper and Si02 passivated wafers.

The bismaleimide compound of the present invention is represented by one of Formulae (1) to (4): N 0 Rif - to, Rd-N--I N-A-N 0 Formula( -N il -T-U-N i: k Fli i I I-o "Q

N-B-N

Formula (3) -9 -r 0 0 Q i i:-N.". 0 ' --ig-Trr'cl ''''N-Rh-N 1 n i 0 6 d m Formula (4) wherein: A and B are independently and at each occurrence independently from each other a binding unit comprising one or more of an aliphatic, aromatic, or siloxane moiety, wherein optionally one or more of A and B contains a cardo center or spiro center; Z is A or B; Ra and RI" are independently and at each occurrence independently from each other a binding unit comprising one or more of an aliphatic, aromatic, or siloxane moiety; Ra is Ra or Rb, R1 is H or alkyl having 'I to 5 carbon atoms, preferably H or CH3; R2 is H or alkyl having '1 to 5 carbon atoms, preferably H or CH3; n is an integer from 1 to 60, preferably 1 to 50, more preferably 2 to 30, and most preferably 3 to 20; and m is an integer from 1 to 60, preferably 1 to 50; more preferably 2 to 30; and most preferably 3 to 20.

Said bismaieimide compounds are used as monomer compounds to form a new class of dielectric polymer material. Said dielectric polymer material is prepared by the following method; which also forms part of the present invention: Method for forming a dielectric polymer material comprising the following steps: -10 - (i) providing a formulation comprising one or more bismaleimide compound according to the present invention; and 00 curing said formulation.

Moreover, a dielectric polymer material is provided, which is obtainable or obtained by the above-mentioned method for forming a dielectric polymer material.

Beyond that; a dielectric polymer material is provided, which comprises at least one repeating unit; which is derived from the bismaleimide compound according to the present invention.

Finally, an electronic device is provided comprising a dielectric polymer material according to the present invention.

Preferred embodiments of the present invention are described hereinafter and in the dependent claims.

Brief description of the figures

Fig, 1: Schematic view of a fan-out wafer-level packaging (\ALP) structure. Fig, 2: DMA measurement of polymer material obtained from Oligomer BM8 cured together with 10 wt.-% BMI 689 and 5 wt.-%Irgacure OXE-02. Fig, 3: DMA measurement of polymer material obtained from Oligomer BM 9 cured together with 10 wt.-% BMI 689 and 5 wt.-% irgacure OXE-02.

Detailed description

Definitions The term "binding unit" as used herein, relates to an organic structural unit that connects two or more parts of a molecule. A binding unit is typically composed of different moieties. A binding unit may be divalent or polyvalent, preferably divalent or tetravalent.

The term "aliphatic moiety' cS used herein, relates to a linear; branched, cyclic or bridged cyclic aliphatic unit which forms part of a structure of a chemical compound. The aliphatic moiety may contain one or more heteroatoms selected from N, 0; S and P. The aliphatic moiety may be unsubstituted or substituted, preferably with one or more substituents selected from the list consisting of -C(0)R"; -0(0)0R"; -NR"Rw, -OR", -Rx, -ON, -F and -Cl, wherein R" = H, C6-014 aryl or 01-014 alkyl, Rw r--H. 06- 014 aryl or 01-014 alkyl and R" = 06-014 aryl 01 01-014 alkyl, preferably R." = H, methyl, ethyl, propyl or phenyl, ft"' = H, methyl, ethyl, propyl or phenyl and Rx = methyl, ethyl; propyl or phenyl. The aliphatic moiety may contain one OF more functional groups, preferably selected from the list consisting of 0=0 double bond, Cr=ti triple bond, amide, carbarnate, carbonate, ester, ether, secondary or tertiary amine, and keto. The aliphatic moiety is typically linked to at least two adjacent further structural units of the chemical compound.

The term "aromaticno *" as used herein, relates to a rnonocyclic or polycyclic aromatic unit which forms part of a structure of a chemical compound. Polycyclic aromatic units include two or more connected aromatic ring systems which are fixed in one plane. An aromatic moiety may be (i) a hydrocarbon aromatic moiety or (ii) a hoteroatorn containing aromatic moiety, also referred to as heteroaromatic moiety. Hydrocarbon aromatic moieties contain an aromatic ring structure made of carbon atoms, whereas heteroarornalic moieties contain an aromatic ring structure, which further comprises one or more heteroatoms selected from N, 0, S and P. The aromatic moiety may be unsubstituted or substituted, preferably with one or more substituents selected from the list consisting of -0(0)R", -0(0)0R", -NR4R"4, -OR": -R', -ON, -F and -Cl, wherein R4= H, 06-014 aryl or 01-014 alkyl, R1/4-4 = H, 06-014 aryl or 01-014 alkyl and R= 06-014 aryl or Ol-014 alkyl, preferably R" = H. methyl, ethyl, propyi or phenyl, RV = H, methyl, ethyl, propyl or phenyl and Rx = methyl, ethyl, propyl or phenyl. The aromatic moiety is typically linked to at least two adjacent further structural units of the chemical compound.

The term "siloxane moiety" as used herein, refers to a structural unit of a chemical compound which comprises at least one Si-O-S linkage. The siloxane moiety may be linear, branched or cyclic. The siloxane moiety may be unsubstituted or substituted; preferably with one or more substituents selected from the list consisting of -C(0)Rv, -O(0)0R", -NR"Rw, -0R", -Rx, -ON, -F and -Cl, wherein R" = H, 06-014 aryl or 01-014 alkyl, FRY' = H. 06014 aryl or Cl-014 alkyl and Ft' = 06-014 aryl or 01-014 alkyl, preferably RY = H, methyl, ethyl, propyl or phenyl, IR*1/4",---H, methyl, ethyl, propyl or phenyl and Fix = methyl, ethyl, propyl or phenyl. The siloxane moiety is typically linked to at least two adjacent further structural units of the chemical compound.

The term "Spiro compound" as used herein, describes compounds having a Spiro center consisting of two rings connected orthogonally through one common quaternary bonding atom. Typically, a carbon atom serves as the spiro center. The simplest spiro compounds are bicyclic or have a bicyclic portion as part of a larger ring system, in either case with the two rings connected through the common quaternary bonding atom defining the Spiro center. The Spiro center, together with adjacent groups attached thereto, forms a so-called "Spiro moiety", which may be regarded as a characteristic structural unit of Spiro compounds. The spiro moiety is typically linked to at least two adjacent further structural units of the chemical compound Polymeric Spiro compounds are also referred to as "spiro polymers".

The term "Garda polymer" as used herein, describes a subgroup of polymers, where carbon atoms in the backbone of the polymer chain are also incorporated into ring structures. These backbone carbon atoms are -13 -quaternary centers (cardo centers) and form part of a so-called "cardo moiety'. As such, the cyclic side group lies perpendicular to the plane of polymer chain, creating a looping structure. The cardo structure is very similar to the spire structure, but has only one ring attached to a cardo center, while two rings are attached to a spiro center. The cardo center, together with adjacent groups attached thereto, forms a so-called "cardo moiety", which may be regarded as a characteristic structural unit of cardo polymers. The cardo moiety is typically linked to at least two adjacent further structural units of the chemical compound.

The term "polymer" includes, but is not limited to, hornopolymers, copolymers, for example, block, random, and alternating copolymers, terpolyrners, quaterpolyrners, etc., and blends and modifications thereof. Furthermore, unless otherwise specifically limited, the term "polymer" shall include all possible configurational isomers of the material. These configurations include, but are not limited to isotactic, syndiotactic, and atactic symmetries. A polymer is a molecule of high relative molecular mass, the structure of which essentially comprises the multiple repetition of units (i.e. repeating units) derived, actually or conceptually, from molecules of low relative mass (i.e. monomers). Polymers are typically mixtures of molecules with different chain lengths and thus have a molar mass distribution.

The term "oligomer" is a molecular complex that consists of a few monomer units, in contrast to a polymer, where the number of monomers is, in principle, unlimited. Dimers, trimers and tetramers are, for instance, oligomers composed of two, three and four monomers, respectively. Oligomers are typically mixtures of molecules with different chain lengths and thus have a molar mass distribution.

-14 -The term "monomer as used herein, refers to a molecule which can undergo polymerization, thereby contributing constitutional units (repeating units) to the essential structure of a polymer or an oligomer.

The term "homopolymer as used herein, stands for a polymer derived from one species of (real, implicit or hypothetical) monomer.

The term "copolymer" as used herein, generally means any polymer derived from more than one species of monomer, wherein the polymer contains more than one species of corresponding repeating unit. In one embodiment the copolymer is the reaction product of two or more species of monomer and thus comprises two or more species of corresponding repeating unit. It is preferred that the copolyrner comprises two, three, four, five or six species of repeating unit. Copolymers that are obtained by copolymerization of three monomer species can also be referred to as terpolymers. Copolymers that are obtained by copolymerization of four monomer species can also be referred to as quaterpolymers. Copolymers may be present as block, random, and/or alternating copolymers.

The term "block copolymer" as used herein, stands for a copolymer, wherein adjacent blocks are constitutionally different! i.e. adjacent blocks comprise repeating units derived from different species of monomer or from the same species of monomer but with a different composition or sequence distribution of repeating units.

Further, the term "random copolymer as used herein, refers to a polymer formed of macromolecules in which the probability of finding a given repeating unit at any given site in the chain is independent of the nature of the adjacent repeating units. Usually, in a random copolymer, the sequence distribution of repeating units follows E3ernoullian statistics.

-15 -The term "alternating copolymer" as used herein, stands for a copolymer consisting of macromolecules comprising two species of repeating units in alternating sequence.

"Electronic packaging" is a major discipline within the held of electronic engineering, and includes a wide variety of technologies. It refers to inserting discrete components, integrated circuits, and MSI (medium-scale integration) and LSI (large-scale integration) chips (usually attached to a lead frame by beam leads) into plates through hole on mu:Weyer circuit boards (also called cards), where they are soldered in place. Packaging of an electronic system must consider protection from mechanical damage, cooling, radio frequency noise emission, protection from electrostatic discharge maintenance, operator convenience, and cost.

The term "microelectronic device" as used herein refers to electronic devices of very small electronic designs and components. Usually, but not always, this means micrometer-scale or smaller These devices typically contain one or more microelectronic components which are made from semiconductor materials and interconnected in a packaged structure to form the microelectronic device. Many electronic components of normal electronic design are available in a microelectronic equivalent. These include transistors, capacitors, inductors, resistors, diodes and naturally insulators and conductors can all be found in microelectronic devices. Unique wiring techniques such as wire bonding are also often used in microelectronics because of the unusually small size of the components, leads and pads.

Preferred embodiments Bisinaleimide compoun.d The present invention relates to a bisrnaleimide compound, which is represented by one of Formulae (1) to (4): i\A-t' Ra Nfl -A-N N Formula (1) 0 0 0 R " 0 R- -A-N-0--hi Formula (2) 9 o 0 El 0 Q Ia, El lI N-R"-C-a-r N-A-N "_N_cric N-B-N -PC-N r,---y-1( Rtl

H 6 d / fl-

Formula (3) B2 Ric n -1-0 0 0 0 1( 1 I ii----,,, .-4; , A-N--,F N-Rb-N i c.65----f( El,,,,c,...---..\:( ??---<r*-* '!' 1 r!-I W '/7-i o d i 0 rip Formula (4) wherein: A and B are independently and at each occurrence independently from each other a binding unit comprising one or more of an aliphatic, aromatic, -17 -or siloxane moiety, wherein optionally one or more of A and B contains a cardo center or Spiro center; Z is A or B; Ra and Rb are independently and at each occurrence independently from each other a binding unit comprising one or more of an aliphatic, aromatic, or siloxane moiety; R2 is Ra or Rn, Ri is H or alkyl haying 1 to 5 carbon atoms, preferably H or CH3; R2 is H or alkyl having 1 to 5 carbon atoms, preferably H or CH3; n is an integer from 1 to 60, preferably 1 to 50; more preferably 2 to 30, and most preferably 3 to 20, and m is an integer from 1 to 60, preferably 1 to 50; more preferably 2 to 30; and most preferably 3 to 20.

The bismaleirnide compounds according to Formula (3) or (4) comprise two different repeating units; which are represented by the repeating units marked by the indices n and m, respectively. The cornpounds may thus be regarded as co-oligomers. Here, the different repeating units may form blocks (block co-oligomer), may alter (alternating co-oligorner) or may be randomly distributed throughout the co-oligomer (random co-oiigorner).

Preferably, A and B are independently and at each occurrence independently from each other a binding unit comprising one or more of an aliphatic or aromatic moiety, wherein optionally A, B, or A and B contains a cardo center or spiro center.

More preferably, A is at each occurrence independently from each other a binding unit comprising one or more of a cyclic aliphatic moiety, which is optionally bridged, or an aromatic moiety, wherein A optionally contains a cardo center or Spiro center; and B is at each occurrence independently from each other a binding unit comprising one or more of a cyclic aliphatic moiety, which is optionally -18 -bridged, or an aromatic moiety, wherein B optionally contains a cardo center or Spiro center; and Z is A or B. In a preferred embodiment of the present invention, A and B are independently and at each occurrence independentiy from each other a substituted or unsubstituted aliphatic moiety having 2 to 100 carbon atoms, a substituted or unsubstituted hydrocarbon aromatic moiety having 6 to 100 carbon atoms, a substituted or unsubstituted heteroaromatic moiety having 4 to 100 carbon atoms, a substituted or unsubstituted siloxane moiety having 2 to 50 silicon atoms, preferably a dimethylsiloxane, methylphenylsiloxane, diphenylsiloxane moiety, or a combination thereof, wherein optionaily one or more of A and B contains a cardo center or spiro center; and Z is A or B. In a more preferred embodiment of the present invention, A and Dare independently and at each occurrence independently from each other a substituted or unsubstituted aliphatic moiety having 2 to 80 carbon atoms, a substituted or unsubstituted hydrocarbon aromatic moiety having 6 to 80 carbon atoms, a substituted or unsubstituted heteroaromatic moiety having 4 to 80 carbon atoms, a substituted or unsubstituted siloxane moiety having 2 to 50 silicon atoms, preferably a dirnethylsilmane, methylphenylsiloxane, diphenylsiloxane moiety, or a combination thereof, wherein optionally one or more of A and B contains a cardo center or Spiro center; and Z is A or B. In a particularly preferred embodiment of the present invention, A is at each occurrence independently from each other a substituted or unsubstituted cyclic aliphatic moiety having 3 to 80 carbon atoms, which is optionaily bridged, a substituted or unsubstituted hydrocarbon aromatic moiety having 6 to 80 carbon atoms, a substituted or unsubstituted heteroaromatic moiety -19 -having 4 to 80 carbon atoms. or a combination thereof, wherein A optionally contains a cardo center or Spiro center; and B is at each occurrence independently from each other a substituted or unsubstituted cyclic aliphatic moiety having 3 Lc 80 carbon atoms, which is optionally bridged, a substituted or unsubstituted hydrocarbon aromatic moiety having 6 to 80 carbon atoms, a substituted or unsubstituted heteroarornatic moiety having 4 to 80 carbon atoms; or a combination thereof, wherein B optionally contains a cardo center or Spiro center; and Z is A or B. It is preferred that A is diFferent from B. Preferably, in Formula (1), (2), (3) and/or (4), A and B are independently and at each occurrence independently from each other represented by Formula (5) _321_(ft,21-322)k-A22 23_,A23)frG24-Formula (5) wherein: A21, A22 and A23 are independently and at each occurrence independently from each other a divalent aromatic group; preferably having 4 to 30 carbon atoms, a divalent aliphatic group, preferably having 2 to 20 carbon atoms, or a divalent mixed aromatic aliphatic group, preferably having 6 to 30 carbon atoms, which may contain one or more heteroatorns selected from 0 arid S and which may be substituted with one or more substituents selected from the list consisting of halogen, preferably F, Cl, Br and I, alkyl having Ito 10 carbon atoms, alkoxy haying 1 to 10 carbon atoms, aryl having 6 to 10 carbon atoms and aryloxy having 6 to 10 carbon atoms; wherein one Or more of A21. A32 and A23 optionally contains a cardo center or spiro center; -20 -G21, G22, G23 and G24 are independently and at each occurrence independently from each other -0-, --S-, -CO-, -(CO) 0, 0-(C0)-, -S-(C0)-, -(C0)-S-, -(C0)-NR:31-, -NR°1-(C0)-, -NR°1-(C0)-NR°2-, -NR°1-(C0)-0-, -0-(C0)-NR°1-, -OCH2-, -CH20-; -CH2S-, -CF20-, -0CF2 CF2S-, --SCF2-, --CH2CH2*, -(CH2)4-, -CF2CH2-, --CH2CF2-, -CF2CF2-, -N=N-, -CH=CRal-, -Cr 1,-cy02_, -CH=CH-(C0)-0-, -0-(C0)-CH=CH-, or a single bond, wherein R°1 and R°2 are independently from each other H or alkyl having 1 to 5 carbon atoms; Y°' and Y°2 are independently from each other H, alkyl having 1 to 5 carbon atoms, phenyl, F, Cl, or ON; and k and I are independently of each other 0, 1, 2, 3 or 4, preferably 0 or 1, more preferably k and I are 1.

Preferably, A21, A22 and A23 are independently and at each occurrence independently from each other represented by one of Formulae (6a) to (6z): Formula (6a) Formula (Sc) Formula (6d) (Lk, Formula (69)

R

Formula (60 (L),1 Formula (6i) (L)q Formula (6 Formula (61) Ph Formula (6p) Formula (6k) (L)q Formula (6m) Formula (6o) Formula (61) Formula (6n) Formula (6g) RAlk RAik RAlk q(L) e\ Formula (6q) Formula (Os) Formula (6r) Formula (6t) Formula (6v) Formula (6x) Formula (6z) -)q (14 Formula (6u) Formula (6w) Formula (6y) wherein represents a b ndino site; -23 -is alkyl or fluoroalkyl having 1 to 5 carbon atoms, halogenyl, Ph or ON, preferably CE13, CF3, F, CI, Ph or ON; RAlk is alkyl or fluoroalkyl having 1 to 5 carbon atoms, preferably CH3 or Ci=3; 0 is 0, S or Ohl2; p is an integer from Ito 12, preferably from 2 to 10, more preferably from 3 to 6, most preferably 7; and q is an integer from 0 to 4, preferably from 0 to 2, more preferably 0 or 1, most preferably 0.

In a preferred embodiment of the present invention, R.° and Rb are independently and at each occurrence independently from each other a substituted or unsubstituted aliphatic moiety having 2 to 100 carbon atoms, a substituted or unsubstituted hydrocarbon aromatic moiety haying 6 to 100 carbon atoms, a substituted or unsubstituted heteroaromatic moiety having 4 to 100 carbon atoms, a substituted or unsubstituted siloxane moiety having 2 to 50 silicon atoms, preferably a dirnethylsiloxane, methylphenyisiloxane, diphenyisiloxane moiety, or a combination thereof; and R2 is Ra or RD.

In a more preferred embodiment of the present invention, Ra and Rb are independently from each other a substituted or unsubstituted aliphatic moiety having 2 to 60 carbon atoms, preferably 10 to 50 carbon atoms, more preferably 10 to 36 carbon atoms, and R2 is Ra or Rb.

It is preferred that Ra is different from Rb.

In a particularly preferred embodiment of the present invention, Ra and Rb are independently and at each occurrence independently from each other represented by Formula (7a) or (7b): -24 -

S CyH2y

Formula (7a) Formula (7b) wherein represents a binding site; x and y are independently from each other an integer from 0 to 10, preferabiy from 1 to 8, more preferably from 3 to 8; and R and RI' are independently from each other a linear alkyl group having to 10 carbon atoms, preferably 1 to 8 carbon atoms, or a branched alkyl group having 3 to 10 carbon atoms, preferably 3 to 8 carbon atoms, more preferably -Cefri 13, -Cshi 17 or -CH2CH(02H5)C4F19.

In a most preferred embodiment of the present invention, Ra and Ric are independently and at each occurrence independently from each other represented by Formula (83) or (8b): C6H13 C8H17 IC81116 Ci31-116+ Formula (8a) Formula (8b) wherein represents a binding site.

Particularly preferred bismaleirnide compounds according to the present invention are: -25 - -26 - -27 - -28 -HN 0 BM9 o, -29 -The bismaleimide compound of the present invention can be prepared by any standard synthesis. Usually, the compound is retrosyntheticaily cut into smaller units and formed stepwise from suitable precursor compounds. For this purpose, known standard reactions such as e.g. amide formation, imide formation, and related add activations, etc. can be used. It has proven to he particularly advantageous to attach the maleimide groups at a later stage of the synthesis, typically at the very last step of the synthesis. By doing so, undesirable side-reactions or premature polymerization of the compound can be avoided.

The ma eirnide group is a functional group capable to undergo a polymerization reaction such as, for example, a radical or ionic chain polymerization, a polyaddition or a polycondensation, or capable to undergo a polymerization analogous reaction such as, for example, an addition or a condensation on a polymer backbone.

Method for forming a dielectric polymer material The present invention further provides a method for forming a dielectric polymer material comprising repeating units derived from one or more of the bismaleimide compound. The dielectric polymer material may be linear or crosslinked.

The method for forming a dielectric polymer material according to the present invention comprises the following steps: providing a formulation comprising one or more bismaleimide compound according to the present invention; and (ii) curing said formulation.

-30 -Preferably, the formulation providestep) further comprises one or more additional compound being capable to react with the bismaleimide compound according to the present invention to preferably form a copolymer. Using basic chemical knowledge, the skilled person is able to find and select for a given bismaleimide compound of the present invention suitable additional compounds which are capable to react with the first mentioned to preferably form a copolymer.

Preferred additional compounds being capable to react with the bismaleimide compound according to the present invention are selected from the list consisting of acrylates, epoxides, olefins, vinyl ethers, vinyl esters, polythiols, polyamines, and polymaleimides.

Preferred acrylates are acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, methyl cyanoacrylate, ethyl acrylate, ethyl methacrylate, ethyl cyanoacrylate, propyl acrylate, propyl methacrylate, propyl cyanoacrylate, butyl acrylate, butyl methacrylate., butyl cyanoacrylate, pentyl acrylate, pentyl methacrylate, pentyl cyanoacrylate, hexyl acrylate, hexyl methacirylate, hexyl cyanoacrylate, heptyl acrylate, heptyl methacrylate, heptyl cyanoacrylate, octyl acrylate; octyl methacrylate, octyl cyanoacrylate, ethylene glycol dimethacrylate, 2-ethylhexyl acrylate, glycidyl methacrylate, (hydroxyethyfiacrylate, (hydroxyethyOrnethacrylate, methyl 2-chloroacrylate; and methyl 2-fluoroacrylate.

Preferred epoxides are ethylene oxide, propylene oxide, butylene oxide, pentylene oxide, hexylene oxide, heptyiene oxide, octylene oxide, glycidarnide, glycidol, styrene oxide 3,4-epoxytetrahydrothiophene.-1,1-dioxide, ethyl 2,3-epoxypropionate, methyl 2-methylglycidate, methyl glycidyl ether, ethyl glycidyl ether; diglycidyl ether; cyclopentene oxide; cyclohexene oxide, cycloheptene oxide, cyclooctene oxide, and sfiloene oxide.

-31 -Preferred olefins are ethylene, propylene, butylene, pentylene, hexylene, heptylene: octylene, isoprene styrene, and vinylethylene.

Preferred vinyl ethers are divinyi ether, methylvinylether, ethylvinylether, propylvinylether; butylvinyiether, pentyivinylether, hexylvinylether, heptylvinylether, and octylvinylether.

Preferred vinyl esters are vinyl formate, vinyl acetate; vinyl prcpanoate; vinyl butanoate; vinyl pentanoate, vinyl hexanoate: vinyl heptanoate, vinyl octanoate, vinyl rionanoate, vinyl decanoate: vinyl acrylate, vinyl methacrylate, vinyl benzoate, vinyl 4-tert-butylbenzoate, vinyl cinnarnate, and vinyl trifiuoroacetate.

Preferred polythiols are organosulfur compounds with two or more Mid functional groups. Particularly preferred polythiols are selected from the list consisting of HS-(CiThl2n)-SH; wherein n = 2 to 20, preferably 2 to 12; CiiE2il-1(SH)3, wherein n = 3 to 20, preferably 3 to 12; HS-Ar-SH, wherein Ar substituted or unsubstituted 06-020 arylene; and HS-(0H2)m-Ar-(C ri2)m-SH, wherein Ar = substituted or unsubstituted 06-020 arylene and nn = 1 to 12.

Preferred polyamines are organoamine compounds with two or more amino functional groups. Particularly preferred polyarnines are selected from the list consisting of Fl2N-(Cd12,0-NH2, wherein n = 2 to 20: preferably 2 to 12; H2N-(C,H2iNH)-NH2, wherein n = 2 to 20, preferably 2 to 12; Crii-12,1(NH2)3; wherein n = 3 to 20, preferably 3 lo 12; H2N-Ar-NH2, wherein Ar = substituted or unsubstituted C6-C2o aryiene: and H2N-(CH2),Ar-(CH2),-H2N, wherein Ar = substituted or unsubstituted 06-020 aryiene and m = 1 to 12.

Preferred pclymaleimides are maleimide end-capped polyimides as described in US 2004/0225026 Al and US 2017/0152418 Al the disclosure of which is herewith incorporated by reference. It is preferred that the polymaleimides are bismaleimides selected from compounds represented by the following Formula (A) or Formula (B): Formula (A) wherein Ri and al are independently selected from the list consisting of structures derived from unsubstituted or substituted aliphatic, acyclic, alkenyl, aryl, heteroaryl, siloxane, boly(butadiene-co-acrylonitrile) and poly(alkylene oxide); X1 to X4 are each independently H or an alkyl group with 1 to 6 C atoms; and n = 0 to 30; Formula (B) wherein R2 and Q2 are independently selected from the list consisting of structures derived from unsubstituted or substituted aliphatic, acyclic, alkenyl, aryl, heteroaryl, siloxane, boly(butadiene-co-acrylonitrile) and poly(alkylene oxide); X5 to X8 are each independently H or an alkyl group with 1 to 6 C atoms; R3 and R4 are each independently H or CH3, wherein at least one of R3 and R4 is CH3; and n = 0 to 30.

In a preferred embodiment of Formula (A) and (B), the structure derived from unsubstituteci or substituted aliphatic, acyclic, alkenyi, aryl, heteroaryl, siloxane, poly(butadiene-co-acrylonitrile) and poly(alkylene oxide) are alkyl group, alkenyi group, alkynyl group, hydroxyl group, oxo -33 -group, alkoxy group, mercapto group, cycioalkyl group, substituted cycloalkyl group, heterocyclic group, substituted heterocyclic group, aryl group, substituted aryl group, heteroaryl group, substituted heteroaryl group, aryloxy group, substituted aryloxy group, halogen, haloalkyl group, cyano group, nitro group, nitrone croup, amino group, amide group, -C(0)H, acyl group, oxyacyi group, carboxyl group, carbarnate group, sulfonyl group, sulfonamide group sulturyl group, or -0(0)-, -S-, -S(0)2-; -0C(0)-0-, -NA-0(0)-, -NAC(0)-NA-, -00(0)-NA-, (in the formula"A is H or an alkyl group with 1 to 6 carbons), and it is preferable that one terminal Preferred subsfituents are alkyl group, alkenyl group, alkynyi group, hydroxyl group, oxo group, aikoxy group, mercapto group, cycloalkyl group, substituted cycloalkyl group, heterocyclic group, substituted heterocyclic group, aryl group, substituted aryl group, heteroaryl group, substituted heteroaryl group, aryloxy group, substituted aryloxy group, halogen, haloalkyl group, cyano group, nitro croup, nitrone group, amino group, amide group, -C(0)H, acyl group, oxyacyl group, carboxyl group, carbamate group, sulfonyl group, sulfonamide group, sulfuryl group, or -S-, -S(0)2-, -0C(0)-0-, -NA-0(0)-, -NAC(0)-NA-, -00(0)-NA-, (in the formula""; is H or an alkyl group with I to 6 carbons), acyl group, oxyacyl group, carboxyl group, carbarnate group, sulfonyl group, sulfonamide group, or sulfuryl group.

In a more preferred embodiment of Formula (A) and (B), R' and R2, and Q1 and Q2 are independently selected from the list consisting of substituted or unsubstituted aliphatic, alicyclic, alkenyl, aromatic, siloxane, poly(butadiene-co-acrylonitrile.), or poly(alkylene oxide) moieties.

Preferred aliphatic moieties are straight or branched chain Cl-Csr., alkylene, more preferably straight or branched chain 01-036 alkylene.

-34 -Preferred alicyclic moieties are both ahphatic and cyclic and contain one or more ail-carbon rings which may be either substituted or unsubstituted and which may be optionally condensed and/or bridged. Preferred alicyclic moieties have 3 to 72 C atoms, more preferably 3 to 36 C atoms.

Particularly preferred alicyclic moieties are represented by -Sp1-Cy-Sp2-, wherein Sp' and Sp2 denote independently of each other alkylene having 1 to 12 C atoms or a single bond; C.3 denotes cycloalkylene haying 3 to 12 C atoms which is optionally mono-or polysubst:tuted by alkyl having 1 to 12 C atoms.

Preferred alkenyl moieties are straight or branched chain hydrocarbyl moieties having at least one carbon-carbon double bond, and haying in the range of about up to 100 C atoms. More preferred alkenyl moieties are C2-C50 alkenylene, most preferably 02-C36 aikenylene.

Preferred aromatic moieties include (i) hydrocarbon aromatic moieties such as arylene groups having 6 to 20 C atoms, more preferably 6 to 14 C atoms, which may be either substituted or unsubstituted, and Op heteroaromatic moieties having 3 to 20 C atoms, preferably 3 to 14 atoms, and one or more heteroatorns selected from N, 0, S and P in the aromatic ring structure, which may be either substituted or unsubstituted.

Preferred siloxane moieties are selected from -[RaRbSi-Ojn-RaRbSi-, wherein RI' and RI) are independently H or Ci-05 alkyl, and n = 1 to 1000, more preferably 1 to 100.

Preferred poly(alkylene oxide) moieties are poly(C1-C12 alkylene oxide) moieties.

Preferably, the molar ratio between the bismaleifnide compounds of the present invention and the additional compounds being capable to react with the bismaleimide compounds in the formulation is from 0.1:100 to 100:0.1.

-35 -It is further preferred that the formulation provided in step (i) comprises one or more inorganic or organic if Preferred inorganic fillers are selected from the list consisting of nitrides, titanates, diamond, oxides, sulfides, sulfites, sulfates, silicates and carbides, which may be surface-modified with a capping went. More preferably, the inorganic filler is selected from the list consisting of AIN, A1203, BN, BaTiO3, B203, ire203, Si02, Ti02, 7102, PbS: SiC, diamond and glass particles, which may be surface-modified with a capping agent. Preferred organic fillers are diamondoids or organic polymer particles. Preferred diamondoids are adamantane (C10/116), (C12H18), BC-8 (CI4H2o), diamantane (C14-123), triarnantane (C13f-124), isotetramantane (022H28), pentarnantane (C261-132 and C251-130), cyclohexamantane (C261-13,0) and super-adamantane (C301-136).

Preferably, the total content of the inorganic or organ.c filler material in the composition is in the range from 0.001 to 90 wt.-%, more preferably 0.01 to 70 wt.-% and most ptreferably 0.01 to 50 wt.-%, based on the total weight of the composition In a preferred embodiment, the formulation is provided in step (i) to a surface of a substrate to form a dielectric polymer material on said surface after curing in step (ii). The substrate is preferably a substrate of an electronic or a microelectronic device.

Preferably, the formulation is provided in step (i) as layer having an average thickness of 0.5 to 50 pm, more preferably 2 to 30 pm, and most preferably 3 to 15 pm, in a single coating.

The method by which the composition is applied in step (i) is not particularly limited. Preferred application methods are dispensing, dipping, screen printing, stencil printing: roller coating, spray coating, slot coating, slit coating, spin coating, gravure printing, flexo printing or inkjet printing.

-36 -The bismaleimide compounds of the present invention may be provided in the form of a formulation suitable for gravure printing, flexo printing and/or ink-jet printing. For the preparation of such formulations, ink base formulations as known from the state of the art can be used.

Alternatively, the bismaleimide compound of the present invention may be provided in the form of a formulation suitable for photolithography. The photolithography process allows the creation of a photo pattern by using light to transfer a geometric pattern from a photomask to a light-curable composition. Typically, such light-curable composition contains a photochemically acfivatable polymerization initiator. For the preparation of such formulations, photoresist base formulations as known from the state of the art can be used.

Without wishing to be bound by theory, curing of the bismaleimide compounds according to the present invention may take place via various types of reaction such as e.g. radical polymerization, ionic polymerization, Michael addition andlor cycloaddition reactions.

It is preferred that the formulation is cured in step (fi) by exposure to heat, preferably at a temperature in the range from 25 to 200t, more preferably at a temperature in the range from 25 to 150GC, and/or by exposure to radiation.

It is further preferred that the formulation contains an initiator for free radical polymerization or an initiator for ionic polymerization.

Preferably, the initiators for radical polymerization are activated thermally by exposure to heat or photochemically by exposure to radiation such as UV and/or visible light.

-37 - Preferred initiators for radical polymerization are: tert-amyl peroxybenzoate, 4,4-azobis(4-cyanovaleric add), 1,1'-azobis(cyclohexanecarbonitrile), 2,2'-azobisisobutyronitrile (AIBN), benzoyl peroxide, 2,2-bis(tertbutylperoxy)butane, 1,1-bis(tert-butylperoxy)cyclohexane, 2,5-bis(tert-butylperoxy)-2,5-dirnethylhexane, 2,5-bis(tert-butylperoxy)-2,5-dimethyl-3* hexyne, bis0-(tert-butylperoxy)-1-methylethylibenzene, 1,1-bis(tertbutylperoxy)-3,3,5-trimethylcyclohexane, tert-butyl hydroperoxide, tert-butyl peracetate, tert-butyl peroxide, tert-butyl peroxybenzoate, tert-butylperoxy isopropyl carbonate, cumene hydroperoxicte, cyclohexanone peroxide, dicumyi peroxide, lauroyl peroxide, 2,4-pentanedione peroxide, per:acetic acid, and potassium persulfate. Typically, such initiators are radical polymerization initiators which may be thermally activated.

Further preferred initiators for radical polymerization are: acetophenone, p- benzil, benzoin, benzophenone, 2-benzoyibenzoic acid, 4,4-bis(diethylarnino)benzophenone, 4,4-bis(dimethylamino)benzophenone, benzoin methyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin ethyl ether, 4-benzoylbenzoic acid, 2,2'-bis(2-chloropheny1)-4,4',5,5'-tetraphenyl-1,2'-biimidazde, methyl 2-benzoylbenzoate, benzodioxol-5-y0-4,6-bis(trichloromethyl)-1,3:5-triazine., 2-benzy1-2-(dimethylamino)-4'-miorpholinobutyrophenone, (±)-camphorquinone, 2-chlorothioxanthone, 4,4'-dichlorobenzophenone, 2,2-Diethoxyacetophenone, 2,2-Dirnethoxy-2-phenylacetophenone, 2,4 diethylthioxanthen-9-one, diphenyi(2,4,6-trimethylbenzoyl)phosphine oxide, 1,4-dibenzoyibenzene, 2-ethylanthraquinone, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-rnethylpropiophenone, 2-hydroxy--4-(2-hydroxyethoxy)-2-methylpropiophenone, 2-isopropyithioxanthone, lithium pheny1(2,4,6-trimethylbenzoyl)phosphinate, 2-methyl-4'-(methylthio)-2-morpholinopropiophenone, 2-isonitrosopropiophenone, 2-phenyl-2-(p-toluenesulfonyl-and phenyibis(2,4,6-trimethylbenzoyl)phosphine oxide.

Typically, such initiators are radical polymerization initiators which may be photoctemically activated.

-38 -Preferred initiators for ionic polymerization are: alkyl lithium compounds, alkyl-amine lithium compounds and pentamethylcyclopentadienyl (Op') complexes of titanium, zirconium and hafnium.

Further preferred initiators for ionic polymerization are: bist:4-tertbutylphenyhiodonium hexafluorophosphate, bis(4-fiuorophenypiodonium trifluoromethanesulfonate, cyclopropyldiphenylsulfonium tetrafluoroborate, dimethylphenacylsulfonium tetrafluoroborate., diphenyliodoniurn hexafluorophosphate, diphenyliodonium hexafluoroarsenate, diphenyliodonium trifluoromethanesulfonate, 2-(3,4-dimethoxystyry1)-4,6-bis(trichiciromethyl)-1,3,5-triazine, 2-[2-(furan-2-yi)vinyfl-4,6-bis(trichloromethyl)-1,3,5-triazine, 4-isopropyl-4rimethyldiphenyliodonium tetrakis(pentafluorophenyl)borate, 242-(5-methylfuran-2-yOvinyl]-4,6- bis(trichioromethyl)-1,3,5-triazine, 2-(4-rnethoxyphenyl)-4,6-bis(trichloromethyl).-1,3,5-triazine, 2-(4-methoxystyryI)-4,6-bis(trichloromethyl)-1,3,5-triazine, (2-methylphenyl)(2,4,6-trirnethylphenypiodonium trifluoromethanesulfonate-, (3-methylphenyl)(2,456-trimethylphenypiodonium trifluoromethanesulfonate, (4-methylphenyl)(2,4,6-trirnethylphenybiodoniurn trifluorornethanesullonate., 4-nitrobenzenediazonium tetrafluoroborate, (4- nitrophenyl)(phenyl)loclonium trifluoromethanesulfonate, triphenylsulfonium tetrafluoroborate, triphenyisulfonium bromide, tri-p-tolylsulfonium hexafluorophosphate, tri-p-tolyisulfonium triflucromethans....sullonate, [3-(trifluoromethyl)phenyll(2,4,6-trimethylphenypiodonium trifluoro- methanesulfonate, and [4-(trifluoromethypplienylp,41,6-trimethyl-phenypiodonium trifluoromethanesulfonate. Typicaily, such initiators are cationic polymerization initiators which may be photochemically activated.

Further preferred initiators for ionic polymerization are: acetophenone benzoyloxime, 1,2-bis(21-methoxypheny1)-2-oxoethyl cyclohexylcarbamate, nifedipine, 2-nitrobenzyl cyclohexylcarbamate, 2-(9-oxoxanthen-2-yl)propionic acid 1,5,7-triazabicyclo[4.4.0]clec-5-ene salt, 2-(9-oxoxanthen- -39 - 2-yl)propionic acid 1,5-diazabicyclo[4 3.0]non-5-ene salt, and 2-(9-oxoxanthen-2-Apropionic acid 1,8-diazabicyclo[5.4.0]undec-7-ene salt. Typically, such initiators are anionic polymerization initiators which may be photoche.mically activated.

Exposure to radiaflon includes exposure to visible light and/or UV light. It is preferred that the visible light is electromagnetic radiation with a wavelength from > 380 to 780 nm, more preferably from > 380 to 500 nm. It is preferred that the UV light is electromagnetic radiation with a wavelength of s 380 nm, more preferably a wavelength from 100 to 380 nm. More preferably, the UV light is selected from UV-A light having a wavelength from 315 to 380 nm, UV-B light having a wavelength from 280 to 315 nm, and UV-C light having a wavelength from 100 to 280 nm. it is preferred that the exposure to radiation includes wavelengths according to g, hi. i lines and/or broadband.

As UV light sources Hg-vapor lamps or UV-lasers are possible, as IR light sources ceramic-emitters or IR-laser diodes are possible and for light in the visible area laser diodes are possible.

Preferred UV light sources are light sources having a) a single wavelength radiation with a maximum of -4--255 nm such as e.g. 254 nm and 185 nm Hg low-pressure discharge lamps, 193 nm ArF excimer laser and 172 nm Xe.2 layer, or b) broad wavelength distribution radiation with a wavelength component of c 255 m such as e.g. non-doped Ha low-pressure discharge lamps.

In a preferred embodiment of the present invention, the light source is a xenon flash light. Preferably, the xenon flash light has a broad emission spectrum with a short wavelength component going down to about 200 nm -40 -Dielectric polymer material There is further provided a dielectric polymer material, which is obtainable or obtained by the above-mentioned method for forming a dielectric polymer material according to the present invention. The polymer material is preferably a linear or crosslinked polymer, more preferably a linear polymer.

There is further provided a dielectric polymer material, which comprises at least one repeating unit derived from the bismaleimide compound of any one of Formula (1), (2), (3) or (4) as defined above.

In a preferred embodiment, the dielectric polymer material comprises at least one repeating unit, which comprises a structural unit represented by one of Formulae, (12): -79-N

-N

Formula (9) N-Ra N \fr 0 0 Formula (10) Formula (11) 0 0 11-Rb-N 11 c A 1 0 6 rn 0 0.

N-Ra-N Formula (12) wherein: A, B, Ra, Rb, n and m have one of the definitions mentioned above for Formulae (1), (2), (3) and (4) or related preferred, more preferred, particularly preferred or most preferred embodiments.

In a preferred embodiment, the dielectric polymer material further contains additional repeating units derived from the additional compounds being capable to react with the bisrnaleirnide compounds as defined above.

Electronic device Moreover there is provided an electronic device comprising a dielectric polymer material according to the present invention. For the electronic device it is preferred that the polymer material forms a dielectric layer. The dielectric layer serves to electrically separate one or more electronic components being part of the electronic device from each other.

Preferably, the electronic device is a microelectronic device and the dielectric polymer material is comprised as a repassivation material in a redistribution layer of the microelectronic device.

-42 -The present invention is further iflustrated by the examples following herein--after which shall in no way be construed as limiting. The skilled person will acknowledge that various modifications, additions and alternations may be made to the invention without departing from the spirit and scope of the invention as defined in the appended claims.

Examples

A Synthesis of building blocks A-1 Synthesis of 2,2:-Q4-hexyl-3-octylcylclohexane-1,2-diyljbis(octane- 8,1-diy1))bis(1,3-dioxolsoindoline-5-carboxylic acid) (1) N. NIV1Pttol uene 0 kr H 2N (1 Ho NH2 (1) o 05'KOH 1,2,4-Benzenetricarboxylic anhydride (GAS: 552-30-7, Merck, 37.4 mmol.

7.2 g) was dissolved in 17 mL N1V1P. PriamineTM 1074 (Croda, 18.7 mmol, g) dissolved in toluene (50 mL), was slowly added and the reaction mixture was heated at reflux using a Dean-Stark apparatus. The crude -43 -product was cooled to r.t., treated with 120 mt. MTBE and washed 3 times with water (3 x 80 mL). The organic layer was dried over Na2SO4, filtered and evaporated under vacuum, resulting 16 9 (97 %) of diacid (1).

Analytics: 'H NMR (700 MHz, Criloroform-d): O = 8.55 (5, 2H), 8.47 (d; 7.7 Hz, 2H), 7.96 (d, J = 7.6 Hz, 2H), 3.71 (d, J-= 7.5 Hz, 4H), 1.96 (s, 2H), 1.69(, J= 7.5, 70 Hz, 4H), 1.54 (s, 2H), 1.44-1.09 (m, 52H), 0.96 -0 76 (m, 6H) ppm.

NMR (176 MHz, Chloroform-d): O = 176.2, 169.2, 167.4, 167.3, 137.9; 136.2, 135.9, 134.8, 132.5, 129.0, 126.2, 125.3, 124.9, 123.3, 49.8, 38.5, 37.4, 37.1, 33.2, 32.5, 32.4, 31.9, 20.4, 29.2, 28.5, 27.1, 26.9, 26.7, porn.

A-.2 Synthesis of 4,4' (1 darnantai 2,2-d'yl)dphenol (2) 30.7, 30.2, 30.1, 29.9, 23.2, 22.7, 21.5, 19.7, 29.7, 29.6, 29.5, 17.6, 14.6, 14.1

HO

3-mercaptopropionic add methanesulfonic add trifluorornethanesulfonic acid toluene 2-Adamantanone (CAS: 7 Merck, 40 mmol, 6.0 g) was added to a rnixture of 25 rit toluene and molten phenol (100 mmol, 9.49) at 500 under a nitrogen atmosphere and stirred until it became homogeneous.

3-Mercaptopropionic acid (3.4 mmol, 0.3 mL), methanesulfenic acid (3 mi.) and trifluoro methane sulfonic acid (0.3 mL) were added dropwise and the reaction mixture was kept at 50°C for 12 h, during which a white solid precipitated. The solid was filtered, washed with hot water and recrystallized from ethanol to afford colorless needles (47% yield).

-44 -Analytics: 1H NMR (500 MHz, DMSO-da): 5 902 (s, 2H), 7.20 -7.15 (m, 4H), 6.60 (d, J= 7.6 Hz, 4H), 3.17 (s, 2H), 1.91 (d, J= 12.3 Hz, 4H), 1.74 (s, 2H), 1.68-1.62 (m, 6H) ppm, A-3 Synthesis of 7,7(-((((1r,3,1-adamantane-2,2-dlybbis(4,1-phenyiene))-bis(oxy))bis (heptan-1-amine) hydrochloride (3) G H3N (1) ted-buty ydro rheptyl) carbarnate DEAD, PPiis THF (2) 4 N Ha in dioxane Lc?.

Tert-butyl (7-hydroxyheptyl) carbamate (Merck, CAS: 173436-02-7, 31 mmol, 7.2 g) was dissolved together with compound (2) (31 mmol, 9.9 g) in THE (30 rnt..) at 0"C. Subsequently; a solution of DEAD (40 wt.-% solution in toluene; 21.1 mt.., 46.5 mmol) and triphenylphosphine (12.2 g; 46.5 rnmol) in THE (50 rnL) was added at 0°C. The reaction mixture was stirred at room temperature. After 24 h the so:vent was evaporated and the resulted crude product was purified by column chromatography on silica gel (AcOEtihexane = 1:8). The boc-protected intermediate product was dissolved in 100 mt.. 4 N HCI in dioxane and stirred at room temperature for 2 h The solvent was evaporated and the resulting crude product was recrystallized in ethanol resulting 16.8 g (88%) as a colorless solid.

Analytics: 1H NMR (500 M ISO-d6): 5 = 7.99 (broad s), 7.30(d, J= 7.6 Hz, 4H), 6.75 (d, J = 7.6 Hz, 4H), 3.56-3.83 (m, 4H), 3.22 (s, 2H), 2.73 -45 - (m, 41-1), 1.90 -1.87 (m, 4H), 1 73 (s, 2H 1.68 -1.65 (m, 12H), 1.55 -1.52 (m, 4H), 1.36 ---1.29 (m, 12H) ppm.

Synthesis of Oligomers B-1 Synthesis of BM8 (1) (3) G H3N 1) P(OPh)3 CaCi, pyridine PriamineIM

NMP

2) maleic anhydride

TEALMSA

p-xylene -46 -rjr

_

rN BM8 if Dicarboxylic acid (1) (8.8 g, 10 mrnol) was dissolved together with CaC12 (2.4 g, 22 mmol), pyridine (6.3 g, 80 mrnol) and triphenyl phosphite (7.8 g, rnmol) in NMP (50 mL). Diamine (3) (12.4 g, 20 mmol) was added and the reaction mixture was stirred at 120°C for 3 h, cooled to room temperature and precipitated by adding 200 mi.. of ethanol. The solid was washed several times with ethanol, hot water and again ethanol and vacuum dried. The intermediate was suspended in p-xylene (50 mt..), carefully mixed with methanesulfonic acid (6.9 g, 72 mmol), triethylamine (7.1 g, 70 mrnol) and rnaleic anhydride (2.5 g, 25 mrnol) and refluxed for 5 h -47 -using a Dean-Stark apparatus. After cooling to room temperature, the product was precipitated by the addition of ethanol (150 mL). The brown resin was received after vacuum drying (BM8) (15 g, 72 W).

Analytics: GPO: Mr:: 3.4 kDa, Myv. 6.4 kDa, P01:1.9. 1H NMR (500 MHz, THF-d) 5 -A 8.34-5.15 (m), 8.06 -7.99 (h), 7.55 (d, J = 7.7 Hz), 7.26 (d, Jr 8 5 Hz), 6.73 (s), 6.70(d, "Jr 8.5 Hz); 3.84(q, Jr 5.9 Hz), 3 68 -3.60 (m), 3.38 (t, J = 6.7 Hz), 3.20 (s), 2.56 (s), 2.07 (d, Jr 12.2 Hz), 1.79 -1.55 (m), 1.51 -1.17 (m), 0.87 (g, Jr, 10.3, 8.2 Hz) ppm.

B-"? Synthesis of BM9 / e ) > 1-12N HaN K Cl \ c iii,, Lim \----, s__ -N, ---\ ) J \

Q

r.../ i ' .7r.'12 ± ( /1\ ''''', (5j

--N -Y-

1, 20 (I) OrNIH.,,,K, H2N1 H3N-r.krui r 0"-"No H (3) 1) P(OPh)3 2) rnaieic anhydride CaCl2 TEANSA pyridine p-xylene PriarnineTM NIsAP -48 -0 BM9 flo -I 6 Method A: Dicarboxylic acid (i) (4.4 g, 5 mmol) was dissolved tooether with CaCl2 (2.4 g, 22 mmol), pyridine (3.2 g, 40 mrnol) and triphenyl phosphite (3.9 g, -49 - 12.5 rnrnol) in NMP (30 mt.). 2,2-Sis[4-(4-aminophenoxy)phenylipropane (GAS: 13080-86-9, Merck, 4.1 a, 10 rnmol) was added and the reaction mixture was stirred at 120nG for 0.5 h. The mixture was cooled to it., treated with additional 30 ml.. NMP, dicarboxylic; acid (1) (4.4 g, 5 rnmol), diamine (3) (6.2 g, 10 rnmol), pyridine (3.2 g; 40 mmol), triphenyl phosphite (3.9 g, 12.5 inmol) and stirred at 12000 for 3 h. Subsequently, it was cooled to it. and precipitated by adding 200 mt.. of ethanol. The solid was washed several times with ethanol, hot water and again ethanol and vacuum dried. The intermediate was suspended in p-xylene (50 mL), carefully mixed with tnethanesulfonic acid (6.9 g, 72 mrnol), triethylamine (Ti g, 70 mmol) and maleic anhydride (2.5 g, 25 mmol) and refluxed fors h using a Dean-Stark apparatus. After cooling to it., the product was precipitated by the addition of ethanol (150 rit). The brown resin was received after vacuum drying (BM9) (12 a, 38 °k).

Analytics: GPO: Mn:kDa, Mw: 18.1 kDa, PDI: 2.0. 1H NMR (500 MHz, THF-ds) 5 = 10.13(s). 5 (s), 8.50 = 7.8 Hz), 8.45 (s), 7.92 (t, J 10.8 Hz), 7.24 (dd, J= 15.2, 8.3 Hz), 6.95 (dt, J = 8.9; 4.4 Hz), 6.89 (d, J =-8.2 Hz), 6.76 (Cl, J = 7.7 Hz), 6.70 (d, J = 3.6 Hz); 3.84 (q, J= 5.9 Hz); 3.66 (dd, J = 14.5, 7.1 Hz), 3.14 (cid, J = 7.3; 4.7 Hz), 1.70-1. 65 (m), 1.44 - 1.15 (rn), 0.97 -0.75 (m) ppm.

Method B: Dicarboxylic acid (1) (4 4g. 5 mmo) was dissolved together with CaCl2 (1.29, 11 mrnol), pyridine (3.1 g, 20 mmol) and triphenyl phosphite (3.9 a 12.5 mmol) in NMP (50 mL). 2,2-Bis[4-(4-aminophenoxy)phenyl]propane (OAS: 13080-86-9, Merck, 2.0g. 5 rnmol) and diamine (3) (3.1 g, 5 mrnol) were added and the reaction mixture was stirred at 12000 for 3 h, cooled to r.t. and precipitated by adding 200 mt. of ethanol. The solid was washed several Limes with ethanol, hot water and again ethanol and vacuum dried.

The intermediate was suspended in p-xylene (50 mL), carefully mixed with methanesuifonic acid (3.5 g, 36 mmol), triethylamine (3.5 g, 35 nimol) and maleic, anhydride (1.2 g, 12.5 mml) and refluxed for 3 h using a Dean-Stark apparatus. After cooling to r.t., the product was precipitated by the addition of ethanol (100 mL), The brown resin was received after vacuum drying (E3M9) (4 g; 25 %) AnaIytics: GPC: Mr: 8.8 kDa, Mw: 12.6 kDa, PDI: 1.9 1H NMR (500 THF-d6) O = 10.24 (s), 9.91 (s), 8.56-8.28 (m), 7.91 (dd, J = 23.5, 73 Hz.); 7.27 (d, J= 8.4 Hz), 7.04 (s), 7.01 (d, J = 8.7 Hz), 6.98 -6.88 (m), 6.78 (di J = 8.7 Hz), 6.74 (d; J = 8.6 Hz); 3.68 (dt, J= 18:8, 6.9 Hz), 3.13 (p, J = 6:5 Hz), 1.85-1.78 (m), 1.72 (s), 1.43 -1,22 (m): 0.98 -0.80 (m) pprn.

Mechanical Testing Dynamic Mechanical Analysis Free standing films were prepared as follows: Concentrated solution of the oligomer mixed with photoinitiator and structural additive BMI 689 (10 wt.%) is slit coated on a glass substrate. The resulted film is firstly dried at room temperature and then at 100°C for 30 min on a hot plate. The film is thermaily cured at 230°C, for 60 minutes and finaliy removed from the substrate after soaking with water. The free standing film is dried at air for 20 h. Dynamic mechanical analysis (DMA) was performed on a Netzsch DMA 242 E instrument in air with a heating rate of 3 K/min.

Results DMA: Formulation with BMW: Tg = 887°C Formulation with BMW: Tg = 105°C Young's dulus and Elongation at Break Young's modulus and elongation at break were measured on a mechanical testing machine (500 N Zwick) using the following parameters: premeasurement: 0.1 N at an extension rate of 10 mm/min; main extension rate of 50 minimin. All experiments were conducted at room temperature using free-standing films prepared with the method described above Film dimensions were 25 mm long, 15 mm wide with a typical film thickness of 40 -60 um Results: Formulation with BM8: &modulus 1.62 MPa with 8% Formulation with 6M9: E-modulus 1.64 MPa with 6% E2B

Conclusion

Formulations of examples BM8 and 8M9 with the structural additive BrAl 689 result in stable films which can be easily thermally cured giving high Tg films with a good Young's modulus which can be used in mechanical buffer applications for electronic packaging as well as RDL passivation. The therrnornechanical properties compared with imide-extended maleimides show a significantly improved Glass transition temperature (Tg) when using similar structural elements.

Films containing the polymer BMI-3000 from Designer Molecules, which is an example of an imide-extended rnaleirnide, show a To of 41°C, which is significantly lower than the Tg of films obtained from the bismale.imide compounds according to the present invention. The same holds true for polymer films obtained only from the structural additive BMI-689 from Designer Molecules, which show a Tg of 42C.

BM1-3000: Where n = 1 to 10 BM-6S9: BM!-689

Claims (7)

1. -53 -Claims 1. Bismaleimide compound; represented by one of Formulae (1) to (4): Formula (1) Hi Formula (2) lo P Q 1 9,..,...",___..k. )1-----'ts.",1 9 i NAN ii fe--N--ei-J,,j-I N.,,c,--...", %..., ' RI---,,\ I-1;^ BI 1 0 0 0 J, Formula (3) 0 0 I-1 o a _ "ii-iitii,.."-N-Fr-N ii 4-e--N B-N "....,-----1( --....."14 i H I-11 O d-0 0 N-R--N * b Formula (4) wherein: A and B are independently and at each occurrence independently from each other a binding unit comprising one or more of an aliphatic, aromatic, or siloxane moiety; Z is A or B; -54 -R° and RI) are independently and at each occurrence independently from each other a binding unit comprising one or more of an aliphatic, aromatic, or siloxane moiety; Rz is IR°or Rb; R1 is H or alkyl having 1 to 5 carbon atoms; R2 is H or alkyl having 1 to 5 carbon atoms; n is an integer from 1 to 60; and m is an integer from 1 to 60.
2. 2. Bismaleimide compound according to claim 1, wherein: A and B are independently and at each occurrence independently from each other a substituted or unsubsfituted aliphatic moiety having 2 to 100 carbon atoms, a substituted or unsubstituted hydrocarbon aromatic moiety having 6 to 100 carbon atoms, a substituted or unsubstituted heteroaromatic moiety having 4 to 100 carbon atoms, a substituted or unsubstituted siloxane moiety having 2 to 50 silicon atoms, or a combination thereof, and Z is A or B.
3. 3. Bismaleimide compound according to claim I or 2, wherein: A and B are at each occurrence independently from each other represented by Formula (5): _021_(A21_G221),(_A22_(G23_A23)1.,G24_ Formula (5) wherein: A21, A22 and Al2.11 are independently and at each occurrence independently from each other a divalent aromatic group; a divalent aliphatic group or a divalent mixed aromatic aliphatic group, which may contain one or more heteroatoms selected from N, 0 and S and which may be substituted with one or more substituents selected from the hst consisting of halogen, alkyl having 1 to 10 carbon atoms, alkoxy having 1 to 10 carbon atoms, aryl haying 6 to 10 carbon atoms and aryloxy haying 6 to 10 carbon atoms; 321 322, 323 and 324 are independently and at each occurrence independently from each other --0-, -S-, -CO-, --S-(C0)--, -(C0)-S-, -0-(O0)-0-, -(C0)-NR°1-, -NR"1-(C0)-NR92-, -NR--(GO;--O--, -0-(O0)-NRe1--, -0C,H2-, -CH20-, -SOH2-; -CH2S-, -CF20-, -0CF2-, -SOF2-, -CH2CH2-, -(OH2)4-, -OF20H2-, -OH2CF2-, -0F2CF2-, -CH=N-, -N=CH--; -N=N-, -OH=OR°1-, -Cr1trOr2-, -OH=C1-1-(C0)-0-, -0-(C0)-C1-1=C1-1-, cia single bond, wherein R°1 and RcY2 are independently from each other H or alkyl haying 1 to 5 carbon atoms; Y°1 and Y°2 are independently from each other it alkyl having 1 to 5 carbon atoms, phenyl, F, CI, or ON; and k and I are independently of each other 0, 1, 2, 3 or 4.
4. 4, Bismaleimide compound according to claim 3, wherein: A21, A22 and A23 are independently and at each occurrence independently from each other represented by one of Formulae (6a) to (6z): --(CHitp la (6a) (L)g \'s I Formula (6b) (L),4 Formula (6c) Formula (6d) RAU( RAEV (1.4q kcz2 _i c*-* * t*-t-) -56 -Fonnua (Se) Formula (6f) RA*. RAIK Formula (60 Formula (6k) Formula (6j) Formula (61) (L)q (L)cj Formula (6m) Formula 6n) Formula (6h) Ph Formula p) -57 -Formula ( Formula ((is) Formula (6w) Formula (60 Formula (6x) Formula (6t) Formula (6v) -58 -Formula (6z) wherein represents a binding site; L is alkyl or fluoroalkyl haying 1 to 5 carbon atoms, halogenyl, Ph or ON; RA''' is alkyl or fluoroalkyl haying Ito 5 carbon atoms; Q is 0, S or CI-12; p is an integer from 1 to 12; and q is an integer from 0 to 4.
5. 5. Bisrnaleimide compound according to oneor more of claims 1 to 4, wherein: Re and Rh are independently and at each occurrence independently from each other a substituted or unsubstituted aliphatic moiety having 2 to 100 carbon atoms, a substituted or unsubstituted hydrocarbon aromatic moiety having 6 to 100 carbon atoms, a substituted or unsubstituted heteroaromatic moiety haying 4 to 100 carbon atoms, a substituted or unsubstituted silaxane moiety haying 2 to 50 silicon atoms, or a combination thereof; and R2 is Raor Rh.
6. 6. Bismaleirnicie compound according to one or more of claims 1 to 5, wherein: RC and Rh are independently from each other a substituted or unsubstituted aliphatic moiety having 2 to 60 carbon atoms; and R2 is Ra or Rh.
7. 7. Bisrnaleimide compound according to one or more of claims 1 to 6, -59 -wherein: R.° and Rh are independently and at each occurrence independently from each other represented by Formula (7a) or (7b): R" Formula (7a) Formula (7b) wherein represents a binding site; x and y are independently from each other an integer from 0 to 10; and RI and R" are independently from each other a linear alkyl group haying 1 to 10 carbon atoms or a branched alkyl group having 3 to 10 carbon atoms: 8: Bismaleimide compound according to one or more of claims '1 to 7, wherein: Ra and Rb are independently and at each occurrence independently from each other represented by Formula (8a) or (8b): C6H13 Formula (8a) Formula (8b) wherein represents a binding site.9. Method for forming a dielecthc polymer material comprising the following steps: -60 - (i) providing a formulation comprising one or more hismaleimide compound according to one or more of claims 1 to and (ii) curing said formulation.10. Method for forming a dielectric polymer material according to claim 9, wherein the formulation further comprises one or more additional compound being capable to react with the bismaleirnide compound.11. Method for forming a dielertric polymer material according to claim 9 or 10, wherein the formulation comprises one or more inorganic or organic Ii Hers.12. Dielectric polymer material, obtainable by the method according any one of claims 9 to 11.13. Dielectric polymer material comprising at least one repeating unit, which is derived from the bismaleimide compound as defined in any one of claims Ito 8.14. Dielectric polymer material according to claim 13, wherein the repeating unit comprises a structural unit represented by one of Formulae (9) to (12): cs 9 1 r,R -- N--A---N I C--Formula (9) -61 -HEFormula (10) Formula (11) :"-) td_J mwherein A, B, R", Rt, n and m are defined as in any one of claims 1 to a 15. Electronic device comprising a dielectric polymer material according to any one of claims 12 to 14.16. Electronic device according to claim 15, wherein the electronic device is a microelectronic device and the dielectric polymer material is comprised as a repassivafion material in a redistribution layer of the microelectronic device. 0 0A N" N-Ra-N'H jfl-Formula (12)