A polyimide resin composition comprising a polyimide resin (A) and at least one 1H-tetrazole (B) selected from the group consisting of 1H-tetrazole, 5,5xe2x80x2-bis-1H-tetrazole, and derivatives thereof, and having an excellent rust preventing effect on copper and copper alloys.

The present invention relates to polyimide resin compositions for electronic materials, which have excellent effects on copper and copper alloys for preventing rust, which form films that are easily dissolved and removed, and which form closely adhering cured films. The polyimide resin compositions according to the present invention can be suitably used in applications for forming layer insulation films, protective films and the like on substrates of semiconductor devices and the like.
In the present invention, the polyimide resins mean not only polyimide in a narrow sense, but also polyimide precursors such as polyamide acids, photosensitive polyimide resins, and the like. The photosensitive polyimide resins include those containing a photosensitive auxiliary, a photopolymerization initiator, a sensitizer and the like.
The polyimide resins have advantages such as low dielectric constant, excellent film-forming properties on a large substrate, high heat resistance and high chemical resistance and are hence used in wide fields as insulating materials and materials for protective films for electronic parts. In semiconductor devices such as IC, LSI, power diode and GTO thyristor, a polyimide film is used as a layer insulation film, passivation film or junction coating. A polyimide film is used as a layer insulation film or protective film in IC-mounted substrates for computers, thermal heads, line sensors, and high performance substrates for COG type liquid crystal televisions and the like.
In the case of a photoresist, it is separated and removed after its role is accomplished in an etching process. However, a layer insulation film, a passivation film or the like in a semiconductor device remains unremoved as a permanent film, and is hence required to have high electrical and mechanical properties. These films must also resist a high temperature (300-350xc2x0 C.) applied in a fabrication process of the semiconductor. The polyimide film is suitable for such a purpose. Polyimide varnishes for formation of polyimide films enjoy an increasing demand in a field of electrical insulating coating.
The polyimide film is generally formed by coating a substrate with a varnish of a polyamide acid (polyamic acid), which is a precursor of polyimide, to form a film and then dehydrating the polyamide acid to cyclize it, thereby polyimidating it. In order to selectively provide a polyimide film at a minute part, it is necessary to form a coating film of a polyamide acid on the whole surface of a substrate, form a pattern on the surface with a photo-resist and etch the polyamide acid with hydrazine or the like.
On the other hand, photosensitive polyimide resins the solubility of which is changed by irradiation of light have been developed in recent years. For example, photosensitive polyimide resin compositions obtained by adding a photo-crosslinking agent to a polyamide acid, polyimide precursors obtained by introducing an acryloyl group into a polyamide acid (Japanese Patent Publication Nos. 30207/1980 and 41422/1980), polyimide precursors obtained by introducing an acryloyl group in the form of a salt into a polyamide acid (Japanese Patent Publication No. 52822/1984), and polyimide precursors obtained by introducing an o-nitrobenzyl ester group into a polyamide acid have been proposed. When such a photosensitive polyimide resin (precursor) is used, a pattern is formed by irradiation of light, and the polyimide resin is cyclized by a heat treatment, thereby forming polyimide.
A method of imparting photosensitivity to polyimide itself, not to a polyimide precursor has been recently developed. Since polyimide is difficult to be dissolved in a solvent, it has been proposed, for example, to use an asymmetric diamine, thereby obtaining solvent-soluble polyimide, or to obtain polyimide, which is soluble in a solvent and has photosensitivity, from benzophenone-tetracarboxylic acid anhydride and an aromatic diamine.
However, the polyimide resins (polyimide and polyimide precursors) have been found to have corrosiveness against metals such as copper and copper alloys (brass and the like), which are in use as conductive materials. The corrosiveness is caused by the fact that a polyamide acid as a polyimide precursor contains carboxyl groups, and the carboxyl groups often remain even after its polyimidation. These carboxyl groups react with copper and copper alloys to corrode them.
Accordingly, for example, when a varnish containing a polyamide acid is used to form a layer insulation film for a multilayer distributing board, a corroding action and generation of copper ions occur in copper or a copper alloy coming into contact with the coating film during the process of heat curing (polyimidation) or after the curing, thereby causing various problems such as insulation failure, breaking of wire, short, rust at metal parts, lowing in adhesion of the film and deterioration of physical properties of the film.
When a varnish of a photosensitive polyamide acid is used to form a film of polyimide, the film tend to remain at unexposed portions thereof upon development due to the reaction of the carboxyl group in the polyamide acid with copper or a copper alloy, so that a difficulty may be encountered on the formation of a good pattern in some cases. More specifically, when the carboxyl group in the polyamide acid is reacted with copper, carboxyl copper (copper salt) is formed. The polyamide acid, in which carboxyl copper has been formed, is lowered in its own solubility in solvents, which forms the cause that a film formed remains undissolved at unexposed portions thereof when development is conducted with a solvent after exposure.
The carboxyl copper is oxidized by dissolved oxygen to form a bivalent copper ion. The copper ion forms the causes of not only the reduction in electrical insulating property, but also lowering in the molecular weight of polyimide formed, lowering in the physical properties and adhesion of the film, and the like. It has been reported that when the bivalent copper ion is combined with an acrylic monomer, migration of an electron occurs to conduct radical polymerization (Chem. Commun., 1968, 273). Even in the photosensitive polyamide acids, those having an acryloyl group as a photosensitive group tend to incur the retention of a film formed at unexposed portions thereof upon development under the influence of the copper ion in particular.
In order to improve the adhesion between a substrate and a polyimide film, some proposals have heretofore been made. For example, it has been proposed to provide a layer of a silane coupling agent on the surface of a copper layer, thereby improving its adhesion to a polyimide film (Japanese Patent Application Laid-Open No. 174439/1989), to add a compound selected from among benzotriazole, 1,2,4-triazole, and these derivatives to a polyamide acid, thereby restraining corrosiveness of the polyamide acid (Japanese Patent Application Laid-Open No. 228359/1990) and to add a silane coupling agent to a polyamide acid varnish, thereby improving the adhesion of a polyimide film formed to a substrate (Japanese Patent Application Laid-Open No. 157286/1985).
However, the varnishes containing these compounds involve a problem that their storage stability is deteriorated. In particular, a silane coupling agent is unstable to humidity. Therefore, the polyamide acid varnish, to which the silane coupling agent is added, involves a problem as to storage stability.
In a method of using the photosensitive polyamide acid to form a polyimide pattern on a copper wiring, in some cases, a film of the polyamide acid may have remained undissolved at unexposed portions thereof upon development due to the migration of a copper ion caused by the reaction of a carboxyl group in the polyamide acid with copper, or humidity resistance of a polyimide film formed and its adhesion to the copper wiring may have been deteriorated. Therefore, it has been generally conducted to plate the copper wiring with chromium or the like where the photosensitive polyamide acid is used. In addition, it has been proposed to conduct patterning of a polyamide acid film on a copper layer subjected to a surface treatment by, for example, a method in which the surface of the copper layer is subjected to a surface treatment with a silicon compound having an amino group (Japanese Patent Application Laid-Open No. 242613/1994), or a method in which the surface of the copper layer is treated with oxygen or a chemical to form a film of copper oxide (Japanese Patent Application Laid-Open No. 198559/1993).
Since the method of subjecting the surface of the copper layer to the plating treatment and the method of subjecting the surface of the copper layer to the chemical treatment to form the copper oxide film thereon increase the number of steps, however, their workability and profitability become poor. Therefore, such method are not preferred.
It has also been known to treat the surface of a copper layer with a rust preventive. Many of rust preventives are composed of a basic compound such as an amine compound, a sulfur-containing compound having a coordinating effect on a copper atom, the sodium salt of an organic carboxylic acid, a hydrazine derivative, or a phenol derivative.
However, the amine compound reacts to the carboxyl group in the polyamide acid to reduce its rust preventing effect. As a result, the formation of copper ions can not be completely prevented. In particular, its effect on the photosensitive polyamide acid in which a polymerizable acrylate site is present is insufficient. The sulfur-containing compound, sodium salt of the organic carboxylic acid, hydrazine derivative and phenol derivative are insufficient in rust preventing effect and moreover form the cause of corrosion where a sulfur atom or a sodium atom remains in the resulting insulating film.
It is an object of the present invention to provide a polyimide resin composition for electronic materials, which has excellent effects on copper and copper alloys for preventing rust, which forms a film that is easily dissolved and removed, and which forms a cured film that closely adheres to a surface, in the absence of plating and surface treatment with a rust preventative.
The present inventors have carried out an extensive investigation with a view toward overcoming the above-described problems involved in the prior art. As a result, it has been found that the above object can be achieved by containing a 1H-tetrazole such as 1H-tetrazole, 5,5xe2x80x2-bis-1H-tetrazole, or a derivative thereof in a polyimide resin such as a polyamide acid, solvent-soluble polyimide, photosensitive polyamide acid, photosensitive polyamide acid ester or photosensitive polyimide. The resin composition obtained by compounding the 1H-tetrazole into any of these polyimides and polyimide precursors is generally used as a solution (varnish) with the individual components evenly dissolved in a solvent.
The polyimide resin composition, in which the 1H-tetrazole is compounded, has an excellent corrosion preventing effect on copper and copper alloys. A photosensitive resin composition according to the present invention, such as a photosensitive polyamide acid resin composition, permits the formation of a film excellent in effect of preventing the film from remaining at unexposed portions thereof and adhesion to a substrate without lowering its sensitivity and resolution. Besides, a film obtained from the polyimide resin composition according to the present invention is improved in elongation at break.
The present invention has been led to completion on the basis of these findings.
According to the present invention, there is thus provided a polyimide resin composition comprising a polyimide resin (A) and at least one 1H-tetrazole (B) selected from the group consisting of 1H-tetrazole, 5,5xe2x80x2-bis-1H-tetrazole, and derivatives thereof.
The polyimide resin useful in the practice of the present invention may preferably be at least one polyimide resin selected from the group consisting of polyamide acids, solvent-soluble polyimides, photosensitive polyamide acids, photosensitive polyamide acid esters and photosensitive polyimides.
The present invention will hereinafter be described in detail.
1H-Tetrazole
The greatest feature of the present invention resides in that a 1H-tetrazole such as 1H-tetrazole, 5,5xe2x80x2-bis-1H-tetrazole, or a derivative thereof is added to a polyimide resin such as a polyamide acid, solvent-soluble polyimide, photosensitive polyamide acid, photosensitive polyamide acid ester or photosensitive polyimide, thereby preventing corrosion against copper and copper alloys, and in its turn improving the adhesion of a polyimide film cured to a substrate and preventing a photosensitive film formed from remaining at unexposed portions without being dissolved.
1H-Tetrazole and derivatives thereof are compounds represented by the following formula (1):
5,5xe2x80x2-Bis-1H-tetrazole and derivatives thereof are compounds represented by the following formula (2):
In these formulae (1) and (2), the definitions of R1 and R2 are as follows.
Definition of R1
In the formulae (1) and (2), R1 is a hydrogen atom, an alkyl group having 1-10 carbon atoms, an alkenyl group having 2-10 carbon atoms, an allyl group having 3-10 carbon atoms, an alicyclic group having 3-6 carbon atoms, a phenyl group, a substituted phenyl group represented by the following formula (3):
wherein n is an integer of 1-3, and X is an alkyl group having 1-10 carbon atoms, an alkoxyl group having 1-10 carbon atoms, xe2x80x94NRxe2x80x2Rxe2x80x3 (Rxe2x80x2 and Rxe2x80x3 are independently a hydrogen atom or a methyl, ethyl, acetyl or ethylcarbonyl group), xe2x80x94COOH, xe2x80x94COOCH3, xe2x80x94NO2, xe2x80x94OH, xe2x80x94SH or xe2x80x94SCH3, or a substituted methyl group represented by the following formula (4):
"Parenopenst"CH2"Parenclosest"mYxe2x80x83xe2x80x83(4)
wherein m is an integer of 1-10, and Y is xe2x80x94COOH, xe2x80x94NRxe2x80x2Rxe2x80x3 (Rxe2x80x2 and Rxe2x80x3 are independently a hydrogen atom or a methyl, ethyl, acetyl or ethylcarbonyl group), a phenyl group or a substituted phenyl group represented by the formula (3).
Among these substituents, preferable specific examples of R1 include a hydrogen atom; alkyl groups having 1-6 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, s-butyl, t-butyl, pentyl, 3-methyl-1-butyl, hexyl and 4-methyl-1-pentyl groups; alicyclic groups having 3-6 carbon atoms, such as cyclopropyl, cyclopentyl, 2-methylcyclopentyl and cyclohexyl groups; a phenyl group; substituted phenyl groups represented by the general formula (3) in which n is 1 or 2, and X is an alkyl group having 1-6 carbon atoms, amino group, methylamino group, acetamide group, xe2x80x94SH or xe2x80x94OH, for example, methylphenyl, dimethylphenyl, butylphenyl, t-butylphenyl, aminophenyl, aminomethylphenyl, acetamidophenyl, mercaptophenyl and hydroxyphenyl groups; and substituted methyl groups represented by the general formula (4) in which m is 1 or 2, and Y is a phenyl, amino, methylamino, dimethylamino or acetamide group, for example, aralkyl groups such as benzyl and phenethyl groups, and (substituted) aminomethyl groups such as aminomethyl, aminoethyl, methylaminomethyl, dimethylaminomethyl and acetylaminomethyl groups.
Definition of R2
In the formula (1), R2 is a hydrogen atom, a hydroxyl group, a cyano group, an alkyl group 1-10 carbon atoms, an alkenyl group having 2-10 carbon atoms, an alkinyl group having 2-10 carbon atoms, an alicyclic group having 3-6 carbon atoms, a phenyl group, a substituted phenyl group, xe2x80x94OR3 (R3 is an alkyl group 1-10 carbon atoms, an alkenyl group having 2-10 carbon atoms, an alkinyl group having 2-10 carbon atoms, a phenyl group or a substituted phenyl group represented by the formula (3)), a substituted methyl group represented by the following formula (5):
"Parenopenst"CH2"Parenclosest"kZxe2x80x83xe2x80x83(5)
wherein k is an integer of 1-10, and Z is a halogen atom, an amino group, xe2x80x94NRxe2x80x2Rxe2x80x3 (Rxe2x80x2 and Rxe2x80x3 are independently a hydrogen atom or a methyl, ethyl, acetyl or ethylcarbonyl group), a phenyl group, a substituted phenyl group represented by the formula (3), xe2x80x94SH, xe2x80x94SR4 (R4 is an alkyl group 1-10 carbon atoms, an alkenyl group having 2-10 carbon atoms, an alkinyl group having 2-10 carbon atoms, a phenyl group or a substituted phenyl group represented by the formula (3)), xe2x80x94C(NH2)Hxe2x80x94(CH2)nxe2x80x94CH3 (n: 1-5) or xe2x80x94C(NHCH3)Hxe2x80x94(CH2)nxe2x80x94CH3 (n: 0-5), or a group represented by the following formula (6):
R5xe2x80x94Axe2x80x94xe2x80x83xe2x80x83(6)
wherein A is xe2x80x94COxe2x80x94, xe2x80x94NHCOxe2x80x94, xe2x80x94C(xe2x95x90Nxe2x80x94OH)xe2x80x94, xe2x80x94CH(OH)xe2x80x94, xe2x80x94CH(NH2)xe2x80x94, xe2x80x94CH(Cl)xe2x80x94 or xe2x80x94CH(Br)xe2x80x94, and R5 is an alkyl group having 1-20 carbon atoms, an alkenyl group having 2-20 carbon atoms, an alicyclic group having 3-6 carbon atoms, a phenyl group, a substituent phenyl group represented by the formula (3), a substituted methyl group represented by the formula (5) or a group represented by the following formula (7):
wherein X is an alkyl group having 1-10 carbon atoms, an alkoxyl group having 1-10 carbon atoms, an amino group, xe2x80x94NRxe2x80x2Rxe2x80x3 (Rxe2x80x2 and Rxe2x80x3 are a hydrogen atom or a methyl, ethyl, acetyl or ethylcarbonyl group), xe2x80x94COOH, xe2x80x94COOCH3, xe2x80x94NO2, xe2x80x94OH, xe2x80x94SH or xe2x80x94SCH3.
Preferable specific examples of R2 include a hydrogen atom; a cyano group; alkyl groups having 1-6 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, s-butyl, t-butyl, pentyl, 3-methyl-1-butyl, hexyl and 4-methyl-1-pentyl group; alicyclic groups having 3-6 carbon atoms, such as cyclopropyl, cyclopentyl, 2-methyl-cyclopentyl and cyclohexyl groups; a phenyl group; substituted phenyl groups having a C1-C6 alkyl group, such as methylphenyl, ethylphenyl, propylphenyl, butylphenyl, pentylphenyl and hexylphenyl groups; (substituted) aminophenyl groups such as aminophenyl, methylaminophenyl and acetamidophenyl groups; and substituted methyl groups represented by the general formula (5) in which k is 1 or 2, and Z is a phenyl, amino, methylamino, dimethylamino or acetamide group, for example, aralkyl groups such as benzyl and phenethyl groups, and (substituted) aminomethyl groups such as aminomethyl, aminoethyl, methylaminomethyl, dimethylaminomethyl and acetylaminomethyl groups.
As preferable specific examples of 1H-tetrazole, 5,5xe2x80x2-bis-1H-tetrazole, and derivatives thereof, may be mentioned unsubstituted 1H-tetrazole; 5-substituted 1H-tetrazoles such as 5-methyl-1H-tetrazole, 5-phenyl-1H-tetrazole and 5-amino-1H-tetrazole; 1-substituted 1H-tetrazoles such as 1-methyl-1H-tetrazole; and 1- and 5-disubstituted 1H-tetrazole such as 1-phenyl-5-mercapto-1H-tetrazole. Of these, 1H-tetrazole and 5-substituted 1H-tetrazoles, in which R1 is H, are particularly preferred.
The 1H-tetrazoles used in the present invention have a particularly high effect where R1 is a hydrogen atom. The reason for it is as follows. When a hydrogen atom is bonded to a nitrogen atom at each 1-position of the 1H-tetrazoles, such a hydrogen ion (proton) in an aqueous solution shows acidity of the same degree as acetic acid, and so a salt can be easily formed with a metal or base. Accordingly, the 1H-tetrazoles react to copper or a copper alloy to form copper salts. These copper salts are stable to oxidation and prevent the isolation of a copper ion. In addition, the 1H-tetrazoles are considered to inhibit a reaction of a carboxyl group in the polyamide acid with copper or a copper alloy to prevent the formation of copper carboxylate.
On the other hand, the 1H-tetrazoles in which R1 is another substituent than a hydrogen atom, show basicity and are considered to have an action to neutralize carboxyl groups in the polyamide acid rather than an action on copper. However, even use of such a tetrazole brings about action and effect that the rate of residual film is improved low though its effect is somewhat low.
The 1H-tetrazoles are also effective when they are added to the solvent-soluble polyimide, photosensitive polyimide or photosensitive polyamide acid ester. These polyimide resins are such that the carboxyl groups in the polyamide acid have been converted into imide bonds or ester bonds, and are difficult to cause a reaction with copper. However, their conversion into the imide bonds or ester bonds does generally not reach 100%, and so a small amount of the carboxyl groups may remain in some cases. Besides, it is considered that during storage of these polyimide resins in the form of a solution, the imide bonds or ester bonds are hydrolyzed by water existing in each solution to form carboxyl groups. The 1H-tetrazoles have an effect of inhibiting a reaction of the carboxyl groups thus formed with copper.
The 1H-tetrazoles are generally used in a proportion of 0.05-20 parts by weight, preferably 0.1-5 parts by weight, more preferably 0.3-3.0 parts by weight, per 100 parts by weight (in terms of solids) of the polyimide resin. If this proportion is too low, the effect of the addition becomes small. If the proportion is too high on the other hand, the effect is not brought about correspondingly to such a proportion.
The 1H-tetrazoles are generally added to a solution of the polyimide resin into a resin composition (solution). The resultant composition is used in applications for coating on a substrate or the like to form a film.
Polyimide Resin
In the present invention, a polyamide acid, solvent-soluble polyimide, photosensitive polyamide acid, photosensitive polyamide acid ester or photosensitive polyimide may be used as the polyimide resin.
The polyamide resin useful in the practice of the present invention is generally synthesized by using a tetracarboxylic acid or the acid anhydride thereof as an acid component and a diamine compound as an amine component, and subjecting both components to a condensation reaction at 0-100xc2x0 C. in an organic polar solvent under water-free conditions.
The photosensitive polyamide acid or photosensitive polyamide acid ester can be obtained by a method in which an acryloyl group, which is photopolymerizable, is introduced into a polyamide acid or polyamide acid ester, or a method in which an actinic ray-sensitive functional group is introduced into the above compound at terminals thereof. The photosensitive polyamide acid and photosensitive polyamide acid ester may contain a photopolymerization initiator, a photosensitizer, a photosensitive auxiliary (crosslinking aid) and the like as needed.
As the solvent-soluble polyimide and photosensitive polyimide, those mentioned above in BACKGROUND ART may be used.
Diamine Compound
Examples of the diamine compound include aromatic diamines such as 2,2xe2x80x2-di(p-aminophenyl)-6,6xe2x80x2-bisbenzoxazole, 2,2xe2x80x2-di(p-aminophenyl)-5,5xe2x80x2-bisbenzoxazole, m-phenylenediamine, 1-isopropyl-2,4-phenylenediamine, p-phenylenediamine, 4,4xe2x80x2-diaminodiphenylpropane, 3,3xe2x80x2-diaminodiphenylpropane, 4,4xe2x80x2-diaminodiphenylethane, 3,3xe2x80x2-diaminodiphenylethane, 4,4xe2x80x2-diaminodiphenylmethane, 3,3xe2x80x2-diaminodiphenylmethane, 4,4xe2x80x2-diaminodiphenyl sulfide, 3,3xe2x80x2-diaminodiphenyl sulfide, 4,4xe2x80x2-diaminodiphenyl sulfone, 3,3xe2x80x2-diaminodiphenyl sulfone, 4,4xe2x80x2-diaminodiphenyl ether, 3,3xe2x80x2-diaminodiphenyl ether, benzidine, 4,4xe2x80x3-diamino-p-terphenyl, 3,3xe2x80x3-diamino-p-terphenyl, bis(p-aminocyclohexyl)methane, bis(p-xcex2-amino-t-butylphenyl) ether, bis(p-xcex2-methyl-xcex4-aminopentyl)benzene, p-bis(2-methyl-4-aminopentyl)benzene, p-bis(1,1-dimethyl-5-aminopentyl)benzene, 1,5-diaminonaphthalene, 2,6-diaminonaphthalene, 2,4-bis(xcex2-amino-t-butyl)toluene, 2,4-diaminotoluene, m-xylene-2,5-diamine, p-xylene-2,5-diamine, m-xylylenediamine and p-xylylenediamine; heterocyclic diamines such as 2,6-diaminopyridine, 2,5-diaminopyridine and 2,5-diamino-1,3,4-oxadiazole; alicyclic diamines such as 1,4-diamino-cyclohexane; aliphatic diamines such as piperazine, methylenediamine, ethylenediamine, propylenediamine, 2,2-dimethylpropylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, 2,5-dimethylhexamethylenediamine, 3-methoxyhexamethylenediamine, heptamethylenediamine, 2,5-dimethylheptamethylenediamine, 3-methylheptamethylenediamine, 4,4-dimethylheptamethylenediamine, octamethylenediamine, nonamethylenediamine, 5-methylnonamethylenediamine, 2,5-dimethylnonamethylenediamine, decamethylenediamine, 1,10-diamino-1,10-dimethyldecane, 2,11-diaminododecane, 1,12-diaminooctadecane, 2,12-diaminooctadecane and 2,17-diaminoeicosane; and besides diaminosiloxane, 2,6-diamino-4-carboxylic benzene and 3,3xe2x80x2-diamino-4,4xe2x80x2-dicarboxylic benzidine.
These diamine compounds may be used either singly or in any combination thereof. Of these, 2,2xe2x80x2-di(p-amino-phenyl)-6,6xe2x80x2-bisbenzoxazole and 2,2xe2x80x2-di(p-aminophenyl)-5,5xe2x80x2-bisbenzoxazole are particularly preferred because polymers having low thermal expansiveness and high heat resistance can be provided.
Tetracarboxylic Acid or the Acid Anhydride Thereof
Examples of the tetracarboxylic acid or the acid anhydride thereof Include aromatic tetracarboxylic acid dianhydrides such as pyromellitic dianhydride, 3,3xe2x80x24,4xe2x80x2-benzophenone tetracarboxylic acid dianhydride, benzene-1,2,3,4-tetracarboxylic acid dianhydride, 2,2xe2x80x2,3,3xe2x80x2-benzophenone tetracarboxylic acid dianhydride, 2,3,3xe2x80x24xe2x80x2-benzophenone tetracarboxylic acid dianhydride, naphthalene-2,3,6,7-tetracarboxylic acid dianhydride, naphthalene-1,2,5,6-tetracarboxylic acid dianhydride, naphthalene-1,2,4,5-tetracarboxylic acid dianhydride, naphthalene-1,2,5,8-tetracarboxylic acid dianhydride, naphthalene-1,2,6,7-tetracarboxylic acid dianhydride, 4,8-dimethyl-1,2,3,5,6,7-hexahydronaphthalene-1,2,5,6-tetracarboxylic acid dianhydride, 4,8-dimethyl-1,2,3,5,6,7-hexahydronaphthalene-2,3,6,7-tetracarboxylic acid dianhydride, 2,6-dichloronaphthalene-1,4,5,8-tetracarboxylic acid dianhydride, 2,7-dichloronaphthalene-1,4,5,8-tetracarboxylic acid dianhydride, 2,3,6,7-tetrachloronaphthalene-1,4,5,8-tetracarboxylic acid dianhydride, 1,4,5,8-tetrachloronaphthalene-2,3,6,7-tetracarboxylic acid dianhydride, 3,3xe2x80x2,4,4xe2x80x2-diphenyltetracarboxylic acid dianhydride, 2,2xe2x80x2,3,3xe2x80x2-diphenyltetracarboxylic acid dianhydride, 2,3,3xe2x80x2,4xe2x80x2-diphenyltetracarboxylic acid dianhydride, 2,3xe2x80x3,4,4xe2x80x3-p-terphenyltetracarboxylic acid dianhydride, 2,2xe2x80x3,3,3xe2x80x3-p-terphenyltetracarboxylic acid dianhydride, 2,3,3xe2x80x3,4xe2x80x3-p-terphenyltetracarboxylic acid dianhydride, 2,2-bis(2,3-dicarboxyphenyl)propane dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, bis(2,3-dicarboxyphenyl) ether dianhydride, bis(3,4-dicarboxyphenyl) ether dianhydride, bis(2,3-dicarboxyphenyl)methane dianhydride, bis(3,4-dicarboxyphenyl)methane dianhydride, bis(2,3-dicarboxyphenyl) sulfone dianhydride, bis(3,4-dicarboxyphenyl) sulfone dianhydride, 1,1-bis(2,3-dicarboxyphenyl)ethane dianhydride, 1,1-bis(3,4-dicarboxyphenyl)ethane dianhydride, perylene-2,3,8,9-tetracarboxylic acid dianhydride, perylene-3,4,9,10-tetracarboxylic acid dianhydride, perylene-4,5,10,11-tetracarboxylic acid dianhydride, perylene-5,6,11,12-tetracarboxylic acid dianhydride, phenanthrene-1,2,7,8-tetracarboxylic acid dianhydride, phenanthrene-1,2,6,7-tetracarboxylic acid dianhydride and phenanthrene-1,2,9,10-tetracarboxylic acid dianhydride, and hydrogenated products thereof; alicyclic acid dianhydrides such as cyclopentane-1,2,3,4-tetracarboxylic acid dianhydride, cyclobutanetetracarboxylic acid dianhydride, bicyclo-[2,2,2]oct-7-ene-2-exo,3-exo,5-exo,6-exo-tetracarboxylic acid 2,3:5,6-dianhydride and bicyclo-[2,2,1]heptane-2-exo,3-exo,5-exo,6-exotetracarboxylic acid 2,3:5,6-dianhydride; and heterocyclic derivatives such as pyrazine-2,3,5,6-tetracarboxylic acid dianhydride, pyrrolidine-2,3,4,5-tetracarboxylic acid dianhydride and thiophene-2,3,4,5-tetracarboxylic acid dianhydride.
These compounds may be used either singly or in any combination thereof. Of these, pyromellitic dianhydride, 3,3xe2x80x24,4xe2x80x2-benzophenone tetracarboxylic acid dianhydride and a combination thereof are particularly preferred from the viewpoint of the realization of good low thermal expansiveness, resistance to cracking and resolution.
Introduction of Actinic Ray-sensitive Functional Group
In the present invention, various kinds of photosensitive polyamide acids and photosensitive polyamide acid esters may be used as the polyimide resins. Among these, polyamide acids with an actinic ray-sensitive functional group introduced at terminals thereof are preferred.
As specific examples thereof, may be mentioned polyamide acids with an actinic ray-sensitive functional group introduced at their terminals by causing, for example, a trimellitic acid derivative such as tris(acryloyl)-pentaerythritol anhydrotrimellitate or tris(methacryloyl)-pentaerythritol anhydrotrimellitate (Japanese Patent Application No. 256222/1994); an aminobenzene derivative such as tris(methacryloyl)pentaerythritol p-aminobenzoate (Japanese Patent Application No. 247109/1994); or the like to exist upon the synthesis of a polyamide acid.
Such actinic ray-sensitive functional group-introduced polyamide acids can be synthesized by {circle around (1)} a method in which a trimellitic acid derivative and a tetracarboxylic acid or the acid anhydride thereof are added to a diamine compound, and these components are subjected to a condensation reaction in accordance with a method known per se in the art, {circle around (2)} a method in which a tetracarboxylic acid or the acid anhydride thereof is added to a mixture of a diamine compound and a trimellitic acid derivative, and these components are subjected to a condensation reaction in accordance with a method known per se in the art, or {circle around (3)} a method in which a tetracarboxylic acid or the acid anhydride thereof is added to a mixture of a diamine compound and an aminobenzenecarboxylic acid ester, and these components are subjected to a condensation reaction in accordance with a method known per se in the art.
Preferred as the polyamide acids with an actinic ray-sensitive functional group introduced at each terminal thereof are polyamide acids having, at both terminals thereof, at least one actinic ray-sensitive functional group selected from the group consisting of a group Z1 represented by the following formula (8) and a group Z2 represented by the following formula (9):
wherein X is a single bond, xe2x80x94Oxe2x80x94, xe2x80x94COxe2x80x94, xe2x80x94COOxe2x80x94, xe2x80x94OCOxe2x80x94, xe2x80x94OCOOxe2x80x94, xe2x80x94COCH2Oxe2x80x94, xe2x80x94Sxe2x80x94, xe2x80x94SOxe2x80x94, xe2x80x94SO2xe2x80x94 or xe2x80x94SO2Oxe2x80x94, R3, R4, R5, R6 and R7 are independently a substituent group having a photopolymerizable carbon-carbon double bond, m is 0 or 1, and n is an integer of 1-3;
wherein R3, R4, R5, R6 and R7 are independently a substituent group having a photopolymerizable carbon-carbon double bond, and m is 0 or 1.
In the polyamide acids, those having, at both terminals thereof, the actinic ray-sensitive functional group Z1 represented by the formula (8) are represented by the following formula (10):
wherein R1 is a tetravalent organic group, R2 is a bivalent organic group, k is an integer of 5-10,000, and Z1 is the actinic ray-sensitive functional group represented by the formula (8).
In the polyamide acids, those having, at both terminals thereof, the actinic ray-sensitive functional group Z2 represented by the formula (9) are represented by the following formula (11):
wherein R1 is a tetravalent organic group, R2 is a bivalent organic group, k is an integer of 5-10,000, and Z2 is the actinic ray-sensitive functional group represented by the formula (9).
As examples of an aminobenzene derivative used for introducing the actinic ray-sensitive functional group Z1 represented by the formula (8), may be mentioned compounds represented by the following formula (12):
wherein X is a single bond, xe2x80x94Oxe2x80x94, xe2x80x94COxe2x80x94, xe2x80x94COOxe2x80x94, xe2x80x94OCOxe2x80x94, xe2x80x94OCOOxe2x80x94, xe2x80x94COCH2Oxe2x80x94, xe2x80x94Sxe2x80x94, xe2x80x94SOxe2x80x94, xe2x80x94SO2xe2x80x94 or xe2x80x94SO2Oxe2x80x94, R3, R4, R5, R6 and R7 are independently a substituent group having a photopolymerizable carbon-carbon double bond, m is 0 or 1, and n is an integer of 1-3.
Typical examples of the substituent group having a photopolymerizable carbon-carbon double bond include acryloyloxymethylene and methacryloyloxymethylene groups. Besides, alkenyl groups having 2-6 carbon atoms, such as vinyl, propenyl, isopropenyl, butenyl, pentenyl, hexenyl and 2-ethylbutenyl groups, and substituted groups thereof. Specific examples of substituents capable of being bonded to the alkenyl groups having 2-6 carbon atoms include halogen atoms, a phenyl group, alkenyl groups having 1-4 carbon atoms and alkoxy groups having 1-4 carbon atoms.
Preferable examples of the aminobenzene derivative include aminobenzenecarboxylic esters represented by the following formula (13):
Such an aminobenzenecarboxylic ester can be prepared, for example, in accordance with a process described below. A nitrosobenzoyl halide represented by the formula (14) [in the formula (14), X means a halogen atom]:
and an alcohol represented by the formula (15)
are first subjected to a dehydrohalogenation reaction to obtain a nitrosobenzene represented by the formula (16).
This nitrosobenzene is then reduced, whereby the aminobenzenecarboxylic ester can be obtained.
As examples of a trimellitic acid derivative used for introducing the actinic ray-sensitive functional group Z2 represented by the formula (9), may be mentioned compounds represented by the following formula (17):
wherein R3, R4, R5, R6 and R7 are independently a substituent group having a photopolymerizable carbon-carbon double bond, and m is 0 or 1.
Typical examples of the substituent group having a photopolymerizable carbon-carbon double bond include acryloyloxymethylene and methacryloyloxymethylene groups. Besides, alkenyl groups having 2-6 carbon atoms, such as vinyl, propenyl, isopropenyl, butenyl, pentenyl, hexenyl and 2-ethylbutenyl groups, and substituted groups thereof. Specific examples of substituents capable of being bonded to the alkenyl groups having 2-6 carbon atoms include halogen atoms, a phenyl group, alkenyl groups having 1-4 carbon atoms and alkoxy groups having 1-4 carbon atoms.
Such a trimellitic acid derivative can be synthesized, for example, by subjecting an anhydrotrimellityl halide represented by the formula (18) [in the formula (18), X means a halogen atom]:
and an alcohol represented by the formula (19)
to a dehydrohalogenation reaction (esterification reaction).
Photosensitive Auxiliary
Typical examples of the photosensitive auxiliary include (meth)acrylic compounds such as pentaerythritol triacrylate.
Examples of the acrylic compounds include acrylic acid, methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, cyclohexyl acrylate, benzyl acrylate, carbitol acrylate, methoxyethyl acrylate, ethoxyethyl acrylate, butoxyethyl acrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, butylene glycol monoacrylate, N,N-dimethylaminoethyl acrylate, N,N-diethylaminoethyl acrylate, glycidyl acrylate, tetrahydrofurfuryl acrylate, pentaerythritol monoacrylate, trimethylolpropane monoacrylate, allyl acrylate, 1,3-propylene glycol diacrylate, 1,4-butylene glycol diacrylate, 1,6-hexane glycol diacrylate, neopentyl glycol diacrylate, dipropylene glycol diacrylate, 2,2-bis(4-acryloxydiethoxyphenyl)propane, 2,2-bis(4-acryloxypropoxyphenyl)propane, trimethylolpropane diacrylate, pentaerythritol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, triacrylformal, tetramethylolmethane tetraacrylate, tris(2-hydroxyethyl) isocyanuric acid acrylate,
wherein b means an integer of 1-30,
wherein c and d denote integers satisfying c+d=2xe2x88x9230,
Examples of the methacrylic compounds include methacrylic acid, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, isobutyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, octyl methacrylate, ethylhexyl methacrylate, methoxyethyl methacrylate, ethoxyethyl methacrylate, butoxyethyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxybutyl methacrylate, hydroxypentyl methacrylate, N,N-dimethylamino methacrylate, N,N-diethylamino methacrylate, glycidyl methacrylate, tetrahydrofurfuryl methacrylate, methacryloxypropyltrimethoxysilane, allyl methacrylate, trimethylolpropane monomethacrylate, pentaerythritol monomethacrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexane glycol dimethacrylate, neopentyl glycol dimethacrylate, 2,2-bis(4-methacryloxydiethoxyphenyl)propane, trimethylolpropane dimethacrylate, pentaerythritol dimethacrylate, trimethylolpropane trimethacrylate, pentaerythritol trimethacrylate, tetramethylolmethane tetramethacrylate, tris(2-hydroxyethyl) isocyanuric acid methacrylate,
wherein e means an integer of 1-30,
wherein f and g denote integers satisfying f+g=1xe2x88x9230,
These compounds may be used either singly or in any combination thereof. Of these, pentaerythritol triacrylate and the compound (b=3) represented by the formula (20) are particularly preferred. Commercial products thereof include 3EG-A (product of Kyoeisha Chemical Co., Ltd.) and Biscoat 300 (product of Osaka Organic Chemical Ind. Co., Ltd.).
The photosensitive auxiliary is desirably used in a proportion of 10-40 parts by weight, preferably 15-35 parts by weight, more preferably 20-30 parts by weight, per 100 parts by weight of the polyamide acid.
Solvent
Examples of solvents used in the present invention include polar solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethyl sulfoxide, tetramethylurea, hexamethylphosphoric triamide, and xcex3-butyrolactone.
Besides these polar solvents, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; esters such as methyl acetate, ethyl acetate, butyl acetate, diethyl oxalate and diethyl malonate; ethers such as diethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether and tetrahydrofuran; halogenated hydrocarbons such as dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene and o-dichlorobenzene; and hydrocarbons such as hexane, heptane, octane, benzene, toluene and xylene may also be used.
These solvent may be used either singly or in any combination thereof. Of these, N,N-dimethylacetamide and N-methyl-2-pyrrolidone are particularly preferred. The solvent is used in an amount sufficient to uniformly dissolve the individual components.
Photopolymerization Initiator
Examples of the photopolymerization initiator include Michler""s ketone, benzoin, 2-methylbenzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin butyl ether, 2-t-butylanthraquinone, 1,2-benzo-9,10-anthraquinone, anthraquinone, methylanthraquinone, 4,4xe2x80x2-bis-(diethylamino)benzophenone, acetophenone, benzophenone, thioxanthone, 1,5-acenaphthene, 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-[4-(methylthio)phenyl]-2-morpholino-1-propanone, diacetylbenzyl, benzyldimethyl ketal, benzyldiethyl ketal, diphenyl disulfide, anthracene, phenanthrenequinone, riboflavin tetrabutyrate, acridine orange, erythrosine, 2-isopropylthioxanthone, 2,6-bis(p-diethylaminobenzylidene)-4-methyl-4-azacyclohexanone, 6-bis(p-dimethylaminobenzylidene)-cyclopentanone, 2,6-bis(p-diethylaminobenzylidene)-4-phenylcyclohexanone, aminostyryl ketone, 3-ketocoumarin compounds, biscoumarin compounds, N-phenylglycine, N-phenyldiethanolamine and 3,3xe2x80x2,4,4xe2x80x2-tetra(t-butyl peroxycarbonyl)benzophenone.
The photopolymerization initiator is generally used in a proportion of 0-10 parts by weight, preferably 0.1-5 parts by weight, more preferably 1-5 parts by weight, per 100 parts by weight of the polyamide acid.
Other Additives
In the compositions according to the present invention, various kinds of additives such as an adhesion auxiliary, a leveling agent and a polymerization inhibitor may be further used as needed.
Usage of the Photosensitive Polyimide Resin Composition
The polyimide resin composition according to the present invention is used in the following manner. The composition is first coated on a suitable substrate, for example, a silicon wafer, or a ceramic or aluminum base. Examples of a coating process include spin coating making use of a spin coater, spray coating making use of a spray coater, dipping, printing and roll coating.
In the case where the composition contains the photosensitive polyimide resin, after the composition is then prebaked at a low temperature to dry the coating film, the coating film is exposed to active rays (actinic rays) in the desired pattern form. As the actinic rays, X-rays, electron rays, ultraviolet rays, visible rays and the like may be used. The unexposed portion is then dissolved in a developer to remove it, thereby obtaining a relief pattern.
As the developer, polar solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide and N,N-dimethylformamide, methanol, isopropyl alcohol, and water are used singly or in any combination thereof. In the case where the polyimide resin is alkali-soluble, an alkaline developer or an aqueous alkali solution may be used. As a developing process, there may be used various methods such as spray development, paddle development, dip development and ultrasonic development.
The relief pattern formed by the development is rinsed. Examples of a rinsing liquid include methanol, ethanol, isopropyl alcohol and butyl acetate. A heat treatment is then conducted to form an imide ring, thereby polyimidating the polyamide acid to obtain a final pattern having high heat resistance.
The photosensitive polyimide resin compositions according to the present invention can be used not only in applications related to semiconductor devices, but also as layer insulation films for multi-layer circuits, cover coats for flexible copper-clad sheets, solder resist films, alignment films for liquid crystals, and the like.
In particular, the resin compositions provided by the present invention have marked effects when they are used in the following applications.
(1) A polyamide acid is coated in the form of a varnish on a copper foil or copper wiring to heat and cure it, thereby forming an insulation film of polyimide on the copper layer.
(2) A photosensitive polyamide acid is used to form a pattern of polyimide on a copper or copper alloy wiring.
(3) A solvent-soluble polyimide is used to form a film of polyimide on a copper or copper alloy wiring.
(4) A photosensitive polyamide acid ester is used to form a pattern of polyimide on a copper or copper alloy wiring.
(5) A photosensitive polyimide is used to form a pattern of polyimide on a copper or copper alloy wiring.


A crossfire tube assembly joining adjacent combustors in a gas turbine engine includes an impingement sleeve within which a crossfire tube is centrally disposed. The impingement sleeve is pierced by an array of impingement cooling holes which form a plurality of small jets of cooling air impinging upon, and cooling, the crossfire tube. The space between the impingement sleeve and the crossfire tube forms a flow channel along which the spent impingement air flows in the axial direction before exiting into the interiors of the combustors. A flow dam at the center of the flow channel forces the impingement air to flow toward the ends. An outward flare in a portions of the crossfire tube extending beyond the extremity of the impingement sleeve directs air exiting the flow channel upon an annular flange which supports the crossflow assembly and thus improves cooling in this area.

The present invention relates to gas turbine engines and, more particularly, to gas turbine engines of the type employing a plurality of combustors for burning fuel with air to produce hot, energetic gasses for impingement upon the blades or buckets of a turbine.
A large gas turbine engine conventionally includes a plurality of combustors within each of which a fuel is reacted with a supply of compressed air to produce a plentiful supply of hot gasses. The hot gasses flow at high speed from the combustors to impinge upon the blades or buckets of a rotatable turbine wheel. The turbine wheel rotates an output shaft and also drives a compressor for producing the supply of compressed air. In some gas turbine engines, for example, aircraft jet engines, the output shaft is omitted. The output of the gas turbine is obtained as an exhaust flow which directly propels the aircraft on which it is located.
The combustors are conventionally disposed in a circle about a perimeter of the gas turbine engine. The combustion reaction zones of all adjacent combustors are joined by crossfire, or crossover, tubes which are essentially open tubular structures through which gas and flame are capable of flowing under the influence of a pressure difference in the combustors to which they are connected.
During startup, the shaft of the gas turbine engine is cranked to starting speed by an external energy source. Then, fuel and air are introduced to all of the combustors. A spark plug in one or two of the combustors is fired to start the combustion reaction. As the combustion reaction begins in a combustor, the pressure therein rises due to the production of hot gas. If a neighboring combustor is unlit, the pressure differential produced by the higher pressure in the lit combustor forces hot gas and flame to flow into the unlit combustor. In this way, each adjacent combustor is lit beginning with the lighting of only one or two combustors.
In theory, once all combustors are lit, their pressures equalize and the flow of gas and flame through the crossfire tubes should stop. In practical gas turbine engines, however, differences in geometry, air flow and fuel metering between adjacent combustors may promote continuous gas and flame flow through the crossfire tube joining them. A small amount of flow through the crossfire tubes aids in balancing the pressures and flows from the combustors. The crossfire tubes are connected to the hottest areas of the combustors wherein temperature of, for example, more than 3000 degrees F. may exist. Although the flow of gas and flame through the crossfire tubes does not affect the operation of the gas turbine engine, if a large pressure difference develops between combustors the high gas and flame temperatures flowing through the crossfire tubes are capable of their rapid destruction.
One method for discouraging continuous gas flow in crossfire tubes employs vent holes through the crossfire tubes. Pressurized air in the plenum surrounding the combustors and crossfire tubes flows inward through the vent holes and both cools any gas flowing in the crossfire tubes and tends to equalize the pressure differential along the length thereof. The reduced pressure differential may preclude crossfire gas flow below a given pressure differential. In addition, the air flowing through the vent holes tends to cool the crossfire tube walls to reduce the temperature thereof.
Although they equalize the pressure differential between the ends of the crossfire tube, the vent holes interfere with the primary function of the crossfire tubes in flame propagation. It is thus desirable either to eliminate the vent holes in the crossfire tubes or to limit the amount of vent air capable of flowing therethrough.
Each end of a crossfire tube is affixed in the wall of its combustor using an inward-directed flange. Such flanges tend to become hot and a method for cooling them is desirable.

Impingement cooled crossfire tube assembly in multiple-combustor gas turbine engine


A semiconductor device has at least a square wiring board having a board core made of an insulating material, wires made of a metal and formed on a first surface of the board core, a solder resist film formed on the first surface to cover the wires, and openings formed by partially opening the solder resist film, wherein a plurality of the elongated wires are arranged in parallel on the bottom of the openings, a semiconductor chip having electrodes flip chip connected to the wires are arranged on the bottom of the openings of the wiring board through a conductive bonding material, and an insulating resin is provided for filling an interstice between the wiring board and the semiconductor chip, wherein the wires extend along a width direction orthogonal to a longitudinal direction of the openings, the openings comprise elongated grooves which extend along at least two opposing sides of the square of the wiring board, a pair of opposing edges of the opening along the longitudinal direction define zig-zag edges in which the widths of the opening seem to be longer and shorter in a repeating sequence, and recessed edge portions which recess toward the outside of the opening formed by the zig-zag edges in the width direction correspond to the wires, and protruded edge portions which protrude toward the inside of the opening formed by the zig-zag edges in the width direction correspond to the board core between adjoining the wires.

1. Field of the Invention
The present invention relates to a semiconductor device and a method of manufacturing the semiconductor device, and more particularly, to techniques which are effectively applied to a technique for filling an insulating underfill resin in an interstice between a wiring board and a semiconductor chips which is flip chip connected to the wiring board.
2. Description of the Related Art
As one semiconductor device, a so-called flip chip connection structure is known, where a semiconductor chip is mounted on wires routed on one surface of a wiring board through salient electrodes placed thereon. External electrode terminals are disposed on the other surface of the wiring board. As one flip chip connection structure, JP-A-2000-77471 discloses an example in which gold bump electrodes (gold stud electrodes) disposed on one surface of a semiconductor chip are flip chip mounted to bar-shaped wires (conductor pattern) routed on the top surface of a wiring board through solder.
Patent Document 1 describes a structure which has a connection conductor pattern arranged on a flip chip mounting board, which is made up of a wiring pattern which serves as wires, and connection pads formed continuously to the wiring pattern at positions at which bumps are bonded and having a width wider than the width of the wiring pattern. In this way, when a connection medium (solder) applied on the connection conductor pattern is melted, the solder converges on the connection pads into a lump shape, at the same time the wiring pattern is being formed with a thin film of the connection medium. The bumps are connected to the aforementioned lump-shaped portions.
On the other hand, JP-A-2005-327947 discloses a method for flip chip connecting a semiconductor chip to a wiring board, which involves previously coating an underfill resin on portions of the wiring board, opening up the underfill resin with the semiconductor chip when it is flip chip connected, and filling the interstice between the wiring board and semiconductor chip with the underfill resin.
In semiconductor devices such as CSP (Chip Size Package), BGA (Ball GRid Array) and the like, a structure for flip chip connecting a semiconductor chip on a wiring board is often used in order to reduce the size and thickness of the semiconductor devices. Also, in order to improve the resistance of semiconductor devices to humidity, a structure is employed for filling an interstice between a wiring board and a semiconductor chip with an insulating resin (underfill resin).
A conventional BGA-type semiconductor device has a structure as illustrated in FIG. 1. FIG. 1 illustrates a schematic diagram of the general structure of a BGA-type semiconductor device. Semiconductor device 70 comprises wiring board 71 made, for example, of a glass epoxy resin board, and semiconductor chip 72 electrically connected to the top surface of wiring board 71 through a flip chip connection. Salient electrodes 73 of semiconductor chip 72 are electrically connected to wires (connection pads), not shown. An interstice between semiconductor chip 72 and wiring board 71 is filled with underfill resin 74. Semiconductor chip 72, underfill resin 74 and the like are covered with sealant 75 formed over wiring board 71 and made of an insulating resin. A plurality of external electrode terminals 76 are disposed on the bottom surface of a wiring board.
FIG. 2 illustrates an enlarged cross-sectional view of an end portion of semiconductor device 70 in greater detail. Wiring board 71 has wires 78, 79, respectively, on the top surface and bottom surface of core board 77 made of an insulating glass epoxy resin board. These wires 78, 79 are electrically connected at required locations through conductors 80 extended through board core 77. Also, insulating solder resist films 81, 82 are selectively disposed on the top and bottom surfaces of board core 77. Solder resist films 81, 82 fill up even throughholes in which conductors 80 are formed.
Solder layer 84 is formed on a portion of wire 78 exposed from solder resist film 81 on the top surface of board core 77, and salient electrode 73 of semiconductor chip 72 is fixed on solder layer 84 with solder 86. Salient electrode 73 is formed on the surface of electrode 85 of semiconductor chip 72. In a broader sense, an electrode, when so called, includes salient electrode 73 and electrode 85 as well. As illustrated in FIG. 3, wires 78 are structured to be partially exposed in openings 91 formed by opening solder resist film 81 which was formed on the top surface of board core 77, in an elongated shape. Openings 91 are formed along respective side of square wiring board 71 which includes elongated grooves. Also, a plurality of wires 78 disposed on the bottom of respective openings 91 extend in parallel along a width direction of rectangular openings 91. FIG. 3 omits the illustration of solder layer 84 on the surface of wire 78. A central portion of elongated wire 78 serves as connection pad 83. For convenience, circles are shown in openings 91 formed along the top side of the square illustrated in FIG. 3. These circular areas are those portions at which salient electrodes 73 of semiconductor chip 72 are connected to connection pads 83. To facilitate the understanding, the circles are labeled with the reference numeral of salient electrode 73 for convenience.
Also, as illustrated in FIG. 2, solder layer 88 is formed on top of a portion (connection 87) of wire 79 exposed from solder resist film 82 on the bottom surface of board core 77, and solder ball electrode 89 is fixed on solder ball electrode 89. External electrode terminal 76 is formed by this solder ball electrode 89. In this connection, external electrode terminal 86 is simply called the electrode as well.
Prior to the flip chip connection, an underfill resin (not shown) is selectively coated inside of a frame-shaped portion formed by four openings 91 shown in FIG. 3. Subsequently, as illustrated in FIG. 4A, semiconductor chip 72 is moved down, and semiconductor chip 72 is pressed onto wiring board 71 (see a bold arrow). As a result, underfill resin 74 on wiring board 71 is squeezed by the top surface of semiconductor chip 72 to spread over the top surface of wiring board 71, and flows into openings 91 from solder resist film 81, as indicated by a thin arrow. Also, since underfill resin 74 spreads further, underfill resin 74 spreads from opening 91 onto solder resist film 81, as illustrated in FIG. 4B.
In such flip chip connection, air bubble (void) can sometimes occur in underfill resin 74 filled between wiring board 71 and semiconductor chip 72, as illustrated in FIG. 1.
As a result of analyzing and considering the spreading of underfill resin 74, the inventors found the following fact. Specifically, underfill resin 74 spreads at different speeds (moving speeds) on the surface of board core 77 that is made of a glass epoxy resin and on the surface of solder layer 84 which is a metal, where the speed is higher than on a surface made of glass epoxy resin. Accordingly, a head portion of the underfill resin flows faster on the metal surface area, as compared with the area of board core 77, causing disturbance in the head portion. This disturbance in the moving speed of the underfill resin causes air to be caught up in the head portion, making air bubble (void) 90 more likely to occur.
FIG. 5 illustrates a portion of openings 91. This figure shows the flowing (spreading) state of underfill resin 74. Openings 91 are arranged in a rectangular frame shape, and underfill resin 74 is coated inside of the rectangular frame, with the result that when underfill resin 74 is pressed down by semiconductor chip 72, underfill resin 74 flows into openings 91 from inside edges 91a of openings 91, and again spreads over solder resist film 81 from outer edges 91b. Since solder layer 84 is made of a metal, its surface is flat and encourages underfill resin 74 to flow thereon. On the other hand, since the surface of board core 77 made of a glass epoxy resin is coarse, as compared with the metal surface, underfill resin 74 moves at a speed lower than that on solder layer 84. Accordingly, as illustrated in FIG. 5, the head portion of flowing underfill resin 74 forms advanced head 92 on solder layer 84, and forms delayed head 93 on board core 77, causing the overall head to be undulated. Then, as larger difference a exists between advanced head 92 and delayed head 93, air is more likely to be caught up. Specifically, as the flow is disturbed, the head portion extends to left and right. As advanced head 92 collides with salient electrode 73 stacked on wire 78, advanced head 92 branches into two parts which flow beside salient electrode 73. In this event, the laterally extending head portion delays and extends in front of delayed head 93, and integrates with the extending portion of advanced head 92 which moves forward alongside, thereby catching up air in the flow of underfill resin 74. As a result, air bubble (void) 90 remains in underfill resin 74 after a curing process.

Semiconductor device and method of manufacturing semiconductor device


A sensor element includes a piezoelectric substrate made of a trigonal single crystal and an electrode arranged on the piezoelectric substrate. The substrate surface of the piezoelectric substrate includes an electrical axis of crystal axes. An angle θ formed by the substrate surface and a plane including the electrical axis and an optical axis of the crystal axes is 0°<θ<20°.

1. Technical Field
The present invention relates to a sensor element, a force detecting device and a robot.
2. Related Art
JP-A-4-231827 discloses a known force sensor using a piezoelectric material. As shown in FIG. 15 of JP-A-4-231827 plural measuring elements are arranged on the force sensor. Each measuring element includes a signal electrode 15 held between crystal disks 16. The crystal disks 16 are made of a piezoelectric material and are covered with a metal cover disk 17.
JP-A-4-231827 discloses the use of quartz, which suggests rock crystal, as a piezoelectric material, and maintains that quartz is an optimum material for measuring a multiple-component motive force since quartz receives both compressive and shear stress according to the crystal cut of the quartz. However, there is no description regarding the slicing of the piezoelectric material in a specific crystal direction.

Sensor element, force detecting device, robot and sensor device


A steel member (10) having wear and corrosion resistance through a combination of coatings is disclosed, the steel member (10) being a hardened and tempered steel member having a high tensile strength, at least one selected portion (18) of the steel member (10) coated by thermal spraying with a tungsten carbide-cobalt composition (22) to provide wear and corrosion resistance, the tungsten carbide-cobalt composition (22) being approximately 78-90% tungsten carbide and approximately 10-19% cobalt, and a sacrificial ceramic-metallic coating (24) on the steel member (10) to provide corrosion resistance for the steel member (10). A method of coating a steel member (10) is also disclosed.

Aircraft wheels may include separate drive key members that are attached by bolts to a wheel. The drive key members are engaged by rotors of an aircraft brake. During braking, the drive keys must withstand substantial braking torque as the brake rotors engage the brake stators. The drive key members may be made from hardened and tempered steel to provide a high tensile strength, or a nickel alloy such as Inconel. Inconel drive keys have an inherent corrosion resistance, but are significantly (two to three times) more expensive than steel drive keys. Steel drive keys, while only a fraction of the cost of Inconel drive keys, are subject to corrosion which can result in cracking and failure of the steel.
In some brake systems, steel drive key members are coated with a chromium plating which provides an adequate degree of protection in certain environments. The cost of chromium plating is also low enough that it provides a cost advantage over alloys such as Inconel. However, when carbon-carbon composite brake discs are used in such systems, carbon dust from the brake discs reacts with the chromium plated steel drive keys due to the inherent microcracking in the chromium plating and impairs the effectiveness of the coating. Once the coating is breached, water, cleaning agents and de-icers, for example, may reach the steel member and cause corrosion. The subsequent corrosion plus the high stresses to which the drive keys are subjected results in stress corrosion cracking and may lead to a failure of the drive key.
One way of addressing this problem is by coating the drive key with an electroless nickel plating that forms a barrier over the steel and tungsten carbide coating on the side rails which insulates the steel from the carbon dust. This method may be more expensive than using chrome, but still provides a cost advantage over alloys such as Inconel. Such a method is described, for example, in U.S. Pat. No. 5,931,269 entitled "Aircraft Wheel Part With Corrosion and Wear Resistance," the disclosure of which is hereby incorporated by reference.
It has been found, however, that the electroless nickel coating can be damaged by the stresses applied to the drive keys during use and/or by the scraping of the rotor mounting elements against the drive keys when the rotors are removed for repair or replacement. Once the coating is breached, carbon dust from carbon-carbon brakes reaches the steel beneath the coating and begins to corrode the steel. Repairing electroless nickel is also environmentally unfriendly, time consuming and expensive. Thus, while electroless nickel provides benefits over chromium coatings, it still provides fewer benefits than expensive alloys such as Inconel. It is therefore desirable to provide a steel member, suitable for use as an aircraft wheel rotor drive key, that exhibits corrosion resistance similar to that exhibited by expensive alloys but at a significantly lower cost.

Aircraft wheel part having improved corrosion resistance


A computer tomography system, in addition to conducting a standard computer tomography scan, is capable of producing a shadowgraph prior to conducting the computer tomography examination with the measurement unit in a locked position, as well as one or more real time shadowgraphs during the computer tomography examination. The shadowgraph obtained with the measurement unit in the lock position can then be superimposed with one or more of the real time shadowgraphs obtained during the tomography examination, and the superimposed image displayed, so that patient and/or organ movement arising during the computer tomography examination can be immediately visually perceived.

1. Field of the Invention
The present invention is directed to a computer tomography apparatus, and in particular to such a computer tomography apparatus having the capability of preparing x-ray shadowgraphs.
2. Description of the Prior Art
Computer tomography systems are known in the art which have the capability of producing one or more x-ray shadowgraphs of an examination subject, in order to define the examination region before conducting the computer-tomographic examination. In such known systems, the patient is usually moved through the measurement opening, with the x-ray focus being held at a fixed angular position, and a shadowgraph, i.e., an x-ray projection image, is produced continuously or pulsed line-by-line. This conventional exposure technique for producing a shadowgraph involves the following problem.
Particularly given a fast scan sequence, known as dynamic CT and spiral CT, the processing speed of image processors, even high-performance CT image processors, is usually not adequate to reconstruct the CT tomograms in steps and to display such tomograms in real time on the monitor. This means that the examining attendant has no immediate visual control over the current exposure execution. The momentary slice position, and possible patient motions during the scan sequence, thus cannot be directly perceived. The shadowgraph obtained prior to conducting the CT examination will not include such image information.
It is known to reconstruct both computer tomograms and shadowgraphs for arbitrary projection directions from the data generated during scanning of a measurement volume, and to reproduce the shadowgraph in real time, as described in German OS 41 03 588.

Computer tomography apparatus having means for producing a shadowgraph


One or more tissue bulking devices are implanted to bulk a structure within a patient. The tissue bulking devices may be implanted between the structure and an adventitial layer that at least partially covers the structure, or within the adventitial layer. In some embodiments, the structure is a luminal wall that defines an inner lumen, and the bulking devices are implanted endoscopically via the lumen. In such embodiments, the tissue bulking devices may be implanted between a muscular layer of the luminal wall and an adventitial layer that at least partially covers the luminal wall, or within the adventitial layer. In exemplary embodiments, the luminal wall is the wall of the esophagus of the patient, and the tissue bulking devices are implanted proximate to the lower esophageal sphincter (LES) of the patient to treat gastroesophageal reflux disease (GERD).

Tissue bulking involves the implantation of bulking devices within tissue of a selected structure within a patient. By bulking the tissue of the structure, the bulking devices can alter the function of the structure. For example, bulking devices may be implanted proximate to the lower esophageal sphincter (LES) of a patient to treat gastroesophageal reflux disease (GERD). When implanted proximate to the LES, the bulking devices treat GERD by cooperating with the LES to increase the closing pressure of the LES, thereby reducing the likelihood of reflux flow of fluid from the stomach into the esophagus. As other examples, bulking devices may be implanted near the pyloric sphincter or within the fundus of the stomach to treat obesity, or proximate to a urethral or anal sphincter to treat incontinence.
Luminal walls, such as the esophageal wall, stomach wall, urethral wall and anal wall, include a plurality of layers. The layers of such luminal walls, from the inner lumen outward, include a mucosal layer, submucosal layer, and a muscular layer. Typically, bulking devices implanted within such luminal walls are implanted within the submucosal layer, or between the submucosal and muscular layers. For example, U.S. Pat. No. 6,401,718 discloses an esophageal bulking device for implantation in the submucosa in the vicinity of the LES. It has also been proposed to implant bulking devices within the muscular layer. For example, U.S. Pat. No. 6,595,909 discloses implantation of bulking devices within the muscular layer of the esophagus in the vicinity of the LES.
The submucosal layer comprises soft tissue. Consequently, bulking devices implanted within or directly beneath the submucosal layer may migrate from their intended position, and may even migrate into the mucosal layer. Devices that migrate into the mucosal layer may further migrate into the lumen and be lost, or may be lost as a result of natural sloughing of the mucosal tissue. Moreover, the pronounced protrusions into a lumen caused by bulking devices implanted within or near the submucosal layer can lead to undesirable erosion of the of the mucosal layer and contact between mucosal tissues disposed on opposite sides of the lumen. Even when implanted within the muscular layer of the luminal wall, the pronounced protrusions caused by bulking devices may lead to undesirable mucosal erosion and contact between mucosal tissues disposed on opposite sides of the lumen.
Table 1 below lists documents that disclose techniques for implantation of tissue bulking devices.
TABLE 1Patent NumberInventorsTitle2004/0037887Bourne et al.Bulking agent2004/0037865MillerObesity controlling method2004/0019388StarkebaumMethods and implants forretarding stomach emptyingto treat eating disorders2004/0009224MillerObesity controlling method2003/0199730Silverman et al.Method for treating tissuewith an implant2003/0188755MilbockerTreatment forgastroesophageal disease6,755,869GeitzIntragastric prosthesisfor treatment of morbidobesity6,725,866Johnson et al.Method for treatinggastroesophageal refluxdisease6,660,301Vogel et al.Injectable microspheresfor dermal augmentationand tissue bulking6,595,909Silverman et al.Method for treatingtissue with an implant6,591,838DurginImplant system andmethod for bulking tissue6,540,789Silverman et al.Method for treatingmorbid obesity6,401,718Johnson et al.Submucosal esophagealbulking device6,251,063Silverman et al.Method for treatingwall forminggastrointestinal tract6,238,335Silverman et al.Method for treatinggastroesophageal refluxdisease and apparatusfor use therewith6,098,629Johnson et al.Submucosal esophagealbulking device
All documents listed in Table 1 above are hereby incorporated by reference herein in their respective entireties. As those of ordinary skill in the art will appreciate readily upon reading the Summary of the Invention, Detailed Description of the Preferred Embodiments and Claims set forth below, at least some of the devices and methods disclosed in the patents of Table 1 may be modified advantageously by following the teachings of the present invention.


Concepts and technologies are described herein for determining memory safety of floating-point computations. The concepts and technologies described herein analyze code to determine if any floating-point computations exist in the code, and if so, if the floating-point computations are memory safe. The analysis can include identifying floating-point instructions and conditional statements in the code. The code can be symbolically executed, and behavior of the floating-point instructions and the conditional statements can be monitored to determine if a floating point calculation is ever involved in computation of any memory address during the execution of the code.

Whitebox fuzzing is a form of security testing of application code based upon runtime symbolic execution and constraint solving. Over the years, whitebox fuzzing techniques have been used to identify security vulnerabilities in applications such as compressor-decompressors ("codecs"), image viewers, parsers, media players, and other applications. These types of applications, however, increasingly make use of floating-point instructions available on modern processors. Unfortunately, whitebox fuzzing techniques and constraint solvers are not well-suited to provide efficient analysis and constraint solving of floating-point instructions.
Furthermore, attempts to extend symbolic execution and constraint solving to address floating-point instructions are likely insufficient to solve the looming difficulty of floating-point instruction analysis. For example, as floating-point constraints become more complex and more prevalent, merely extending existing analysis and solving capabilities to analyze floating-point instructions may not address more complex constraints than those currently existing. Thus, such a naïve approach may eventually create more problems and even more pronounced path explosion issues than those already faced.
It is with respect to these and other considerations that the disclosure made herein is presented.

Memory safety of floating-point computations


An optical semiconductor device, including a first optical waveguide with a first width, a second optical waveguide with a second width narrower than the first width with a bending region, and a third optical waveguide with a third width wider than the second width and coupled to the second optical waveguide.

Recently, optical communication systems have employed a wavelength-division multiplexing (WDM) signal processing method. This has dramatically increased transmission capacity of the optical communication systems.
In this case, various optical functional devices may be required to provide advanced functions for the optical signal processing. A bending optical waveguide is used for changing a direction of light propagation in order to achieve smaller-size and higher-density of optical functional elements. Such a bending waveguide may be provided in order to prevent light reflection at an end face of an optical functional element.
Excitation of a higher-order mode in an optical functional element, especially the element that includes an optical branching and coupling element and an interferometer significantly influences the element and eventually deteriorates performance of the optical communication system. The smaller the size of the optical functional element (optical integrated device), the more likely the excited higher-order mode further excites a leakage mode and could cause negative effects.
Accordingly, various methods are proposed to remove an excited higher-order mode.
A method (first method) is proposed in which an S-shaped bending region is provided in one waveguide side of an optical branching and coupling element to remove an excited higher-order mode by making light radiate at the S-shaped bending region.
Another method (second method) is proposed in which a width of one waveguide side of an optical branching and coupling element is made narrower to remove a higher-order mode, and a width of a bending waveguide of a branching part (coupling part) is made wider to suppress a bending loss.
Furthermore, a third method is proposed in which a filter for removing a higher-order mode is provided in one waveguide side of an optical branching and coupling element. For example, when a 1×1 multimode interference (MMI) coupler is provided as a filter for removing a higher-order mode, a fundamental mode passes with little or no excessive loss, however the higher-order mode is subject to substantial loss and may not pass, thus higher-order mode may be selectively removed. The third method, however, increases the number of elements, thereby enlarging the device size. Moreover, an insertion loss due to the filter for removing the higher-order mode and wavelength dependence of the filter for the removing higher-order mode itself is additionally caused, which may influence device characteristics.
Related techniques are disclosed in Japanese Laid-open Patent Publications No. hei. 06-67047, and No. 2006-278770.
Each of the foregoing methods assumes that the higher-order mode is excited and removes a higher-order mode so that the excited higher-order mode may not exert negative influence.
However, it is desirable that a higher-order mode is not excited.
On the other hand, it is found that providing an S-shaped bending region or a bending waveguide excites a higher-order mode at the bending region of the S-shaped bending region or the bending waveguide.
Therefore, it is desirable that excitation of a higher-order mode itself in a bending waveguide be prevented.

Optical semiconductor device, manufacturing method thereof and optical transmission device


An improved graphics system for a graphical user interface in which a plurality of screen objects are displayed is disclosed. Conventional systems comprises targeting means for determining a screen object targeted by the pointer; and selection means for reading a pointer selection and for selecting a screen object. The invention is characterized by the selection means comprising means for selecting a screen object which has been continuously targeted for a predetermined time (pi).

1. Field of the Invention
The present invention relates to a graphics system for providing improved pointer selection accuracy.
2. Description of Prior Art
When selecting an object with a mouse or other pointing device users commonly nudge the pointer while depressing the selection button. This can cause a failure to selection the intended object, or alternatively, inadvertent selection of an object adjacent to the intended object. For example, in FIG. 1, a user who positions a pointer on Object X may inadvertently cause the pointer to move onto Object Y just before clicking the selection button.
This can be a particular problem for partially disabled users or users not accustomed to mice, when selecting small or thin objects. It can also arise in a cluttered environment, or in the presence of unexpectedly selectable objects. A similar problem arises when selecting a moving target.
The present invention relates to a graphics system which remembers the object which the pointer has been pointing at in the recent past.
In a preferred embodiment, an object may be selected even if the pointer is no longer pointing at that object when the selection event is registered. In this case two threshold intervals are used, a pause interval (pi), and a nudge interval (ni). The pause interval prevents incorrect selection, and the nudge interval permits selection even if the pointer is nudged during selection.
In an alternative embodiment, the selection is only successful if the pointer has consistently been pointing at the same object for more than the threshold pause interval (pi) when the selection (e.g., mouse down) event is registered. This prevents selection of the incorrect adjacent object, but does not assist selection of the correct object. Thus, the second mode is a special case of the first mode, with ni=0.
Typical values are pi=0.3 seconds and ni=0.1 second for an uncertain user, pi=0.15 seconds and ni=0.05 seconds for a more experienced user. It will be seen that ni less than pi as otherwise there may be a possibility of an ambiguity in the object to be selected.
In yet another embodiment of the present invention, a graphics system for a graphical user interface (GUI) is disclosed in which screen objects are displayed. The GUI includes targeting means for determining a screen object targeted by the pointer, and selection means for reading a pointer selection and for selecting a screen object.
The graphics system can be characterized by a selection means including means for selecting a screen object which has been continuously targeted for a predetermined time (pi).
Preferably, the targeting means includes means for recording a time at which a screen object becomes targeted. The targeting means also includes means for reading a pointer position before determining which object is targeted.
According to one embodiment of the present invention, the selection means includes means for selecting a screen object which has been continuously targeted for the predetermined time (pi) and for a predetermined time (ni) after it ceases to be targeted. In one embodiment, the predetermined times ni and pi are stored within the graphics system.
According to another embodiment of the present invention, a control panel is associated with the graphics system. The control panel is responsive to user interaction and updating the predetermined times ni and pi according to the interaction. The predetermined time pi is greater than the predetermined time ni.
According to one embodiment of the present invention, the graphics system is embodied in an operating system. Alternatively, the graphics system is embodied in an application wherein the application is one of a general purpose application or a dedicated application.
Further, in another embodiment of the present invention, a computer program product including computer program code stored on a computer readable storage medium for, when executed on a computing device, controls the selection of screen objects, the program code including the graphical system.
In an alternative embodiment of the present invention, a graphics system for a graphical user interface is presented. In this embodiment screen objects are displayed, and a method for selecting a screen object includes determining the screen object targeted by the pointer, and selecting the screen object which has been continuously targeted for a predetermined time (pi), and is responsive to a pointer selection.

Pointer memory for improved selection accuracy

International Business Machines Corporation


A system for commissioning ballasts comprising a wireless device that can be easily transported to any location served by an addressable lighting system. The wireless device allows a user to cycle through a list of uncommissioned ballasts and send a command to a control system to flash the lights connected to each of the ballasts on the list one by one. When a light is observed to flash by the user, the user of the wireless device may then commission the correct ballast with the wireless device. In addition, the user may assign the ballast to a group. In this way, the commissioning of ballasts in, for example, a building is greatly facilitated.

1. The Field of the Invention
The present invention relates generally to systems and methods for commissioning, and more particularly, but not necessarily entirely, to systems and methods for commissioning addressable lighting systems.
2. Background Art
Technology for lighting systems has substantially increased in complexity and capability over the past decade. Traditionally, lights simply provided illumination via simple wiring of light switches and dimmers. More recently, additional functionality has been incorporated into lighting systems to provide additional features and, more importantly, to provide energy conservation. For example, it might be desirable to dim or turn off certain lights to set certain scenes depending on the specific conditions, such as the day of the week, time of day, or even season of the year. In addition, it might be desirable to dim or turn off unnecessary lights, even dim or extinguish only selected lights in a room, to conserve energy.
Digitally addressable lighting is slowly emerging as a popular means for controlling complete lighting environments for a wide variety of different applications. Individual control of each lamp enables the end user to precisely deliver the correct amount of light when and where it is required. Managing the light in this manner potentially allows for a massive reduction in global energy consumption due to lighting. Industrial environments can conserve the total energy required for lighting while actually increasing light quality in certain areas at given times by using modern lighting control systems.
A complete digital dimming system includes the dimming ballasts, in the case of lamps which require a ballast, and a digital control unit for converting information received from a network connection to the communication protocol required by the micro-controller in each ballast. Applications for such systems include building management or studio lighting where it is desired to control a single lamp, or groups of lamps, for conserving energy, performing lamp maintenance or creating precision lighting effects.
Digital dimming ballasts typically include an EMI filter, rectifier, power factor correction, and ballast output stage. The digital ballast also includes a micro-controller for sending and receiving information digitally. The micro-controller functions include storing the ballast address, receiving user instructions, setting the dim reference for the ballast control, receiving status information from the ballast control and sending status information back to the user. The digital ballast potentially allows for complete and precise control of an entire lighting environment.
In the past, the analog 1-10V control interface was the most common industry standard for controlling ballasts. However, the 1-10V control interface has been shown to be inflexible and is slowly being replaced by a new standard known as the Digital Addressable Lighting Interface-protocol or DALI-protocol or just DALI.
DALI is an international standard that has been described in IEC 60929 which establishes the electronic ballast performance requirement. DALI has been designed in a joint effort by many control equipment manufacturers. DALI is advantageous because of its simple wiring control lines and because it allows control over single units (for example, lamps). In addition, the status of each unit may be queried and ascertained.
DALI is currently designed for a maximum of sixty-four single units having individual addresses, a maximum of sixteen groups, and a maximum of sixteen scenes. The "intelligence" has been decentralized to the ballasts, i.e., the values of many set points and lighting values are stored within the individual ballasts. All functions are carried out locally.
Each ballast connected to a DALI controlled system has its own address. An address stands for the definite designation of a unit within a DALI-system. This way each ballast can be contacted individually, although it is connected to a DALI system-line like all the other units. The address assignment, for example, must be effected when the system is put into operation. All units of a system can be contacted at the same time by way of a broadcast.
A differentiation is made between individual addresses and group addresses. Sixty-four individual addresses exist in the DALI-system. Thus, one or several control units can contact individually, i.e. a maximum of sixty-four ballasts. Each ballast may also be part of a maximum of sixteen groups. The plurality of control units can be part of a larger network. In theory, the number of individual ballasts on a network may be unlimited. The DALI control bus comprises two-wires. Any wiring topology can be used, such a line, star or mixed.
One drawback to using the DALI system occurs during the commissioning process. As used herein, the commissioning process entails identifying the physical location of each ballast and its respective address or ID. Typically, all ballasts have an associated address stored by the manufacturer during production. When the DALI system is first activated, each ballast registers with a control unit its respective address. It will be appreciated that the physical location of each ballast may not be known, because there may be up to sixty-four ballasts connected to the control unit. The ballasts may be spread across different rooms, floors or even buildings. In addition, where multiple control units are being used, it may not even be possible to tell which ballasts are controlled by which control units.
In the past, there have been primarily two methods used to commission a DALI system. The first method has been to keep track of the physical location where each ballast is installed in a structure and record its location and the corresponding ballast address. This method has severe drawbacks. First, this method requires that the addresses be printed on the outside of the ballast. Some manufacturers of ballasts may not do this. Secondly, in large scale operations, this may be overly cumbersome and error prone. Next, often the electricians installing the ballasts are not the same individuals who will be initiating the DALI system requiring a high level of cooperation. Finally, the biggest drawback is that even if the addresses and locations are correctly recorded during installation, the DALI system has a randomizing feature that reassigns addresses randomly to each ballast thereby, if such a randomizing feature is purposefully or inadvertently invoked, negating any recorded information.
The second method entails first initiating the DALI system thereby allowing each ballast to register its address with the control unit. Then, a person physically disconnects each lamp, typically by climbing a ladder to reach the lamp, controlled by the system one by one. The control unit will indicate which address has a disconnected lamp. In this manner, the physical location associated with each address can be ascertained. It will be appreciated that in large scale operations, physically disconnecting and reconnecting each lamp one by one is cumbersome and time consuming.
Despite the advantages of known DALI systems, improvements are still being sought. For example, the current known methods of commissioning has significant drawbacks in that it is overly cumbersome and time consuming.
The available methods and devices are thus characterized by several disadvantages that are addressed by the present invention. The present invention minimizes, and in some aspects eliminates, the above-mentioned failures, and other problems, by utilizing the methods and structural features described herein.
The features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by the practice of the invention without undue experimentation. The features and advantages of the invention may be realized and obtained by means of the structures and combinations particularly pointed out in the appended claims.

System and method for commissioning addressable lighting systems