ISSN:0032-3888    

DOI:10.1002/pen.760261602

出版商:Society of Plastics Engineers    

年代:1986

数据来源: WILEY

摘要:

AbstractThe photochemistry of a negative working photoresist, MRL, composed of poly(4‐hydroxystyrene) and an aromatic monoazide compound, 4‐azido‐4′‐methoxychalcone, has been examined, The major products of photolysis of MRL films are primary amine, secondary amine, and poly(4‐hydroxystyrene) with increased molecular weight. The polymeric secondary amines are generated from the nitrene insertion into the backbone carbon‐hydrogen bonds of the polymer. Hydrogen abstraction from the polymer by the nitrene with subsequent polymer radical recombination results in the increase in the molecular weight of the poly(4‐hydroxystyrene), rendering the exposed areas insoluble in both aqueous alkaline and organic developers. Rapid decrease in the dissolution rate of the poly(4‐hy‐droxystyrene) with increasing molecular weight is sep

ISSN:0032-3888    

DOI:10.1002/pen.760261603

出版商:Society of Plastics Engineers    

年代:1986

数据来源: WILEY

摘要:

AbstractSeveral high‐Tg, phenolic copolymers based onN‐(p‐hy‐droxyphenyl)maleimide with various comonomers were prepared, and the properties of a number of these copolymers were studied. The copolymers were 1:1 in composition and were predominantly alternating. The thermal properties of these copolymers were investigated by differential scanning calorimetry and thermal gravimetric analyses. The chain‐stiffening effect of the maleimide group was responsible forTg's of 200°C and above.Tgwas a function of composition and molecular weight. Dissolution rates of thin films of these copolymers were investigated by laser interferometry. The dissolution rates were sensitive to copolymer molecular weight and to the functionality, i. e., the type of phenolic OH groups and the concentration of OH groups present. When these copolymers were used as binders for NDS (diazonaphthoquinone sulfonate) photochemistry, high‐resolution positive images were obtained that were resistant to thermal deformation at

ISSN:0032-3888    

DOI:10.1002/pen.760261604

出版商:Society of Plastics Engineers    

年代:1986

数据来源: WILEY

摘要:

AbstractA new dual image, aqueous developable photoresist can be processed to yield either positive or negative images that are crosslinked and thermally stable to temperatures>300°C. Positive images have similar resolution and processing parameters to conventional positive novolak resists. Negative resists from this system have a number of new and interesting properties that surpass the capabilities of their positive counterparts. In addition to producing highly resolved submicron images, thick coatings of resist can be used to form images with high aspect ratios. By adjusting the exposure of the resist, images with inward sloping wall profiles can be realized. As a result of the images being crosslinked and Insoluble in the resist coating solution, images can be recoated and new images formed over the top of existing patterns to form structures. A hypothetical mechanism that suggests that resist defects caused by dust on the mask or photoresist surface can be reduced In negative mode processing is also presented

ISSN:0032-3888    

DOI:10.1002/pen.760261605

出版商:Society of Plastics Engineers    

年代:1986

数据来源: WILEY

摘要:

AbstractA negative deep UV resist, LMR, has been developed. LMR is a diazonaphthoquinonesulfonate of cresol novolac resin and possesses a high sensitivity of 15 mJ/cm2and a high resolution up to 0.2 μm by contact printing. An important feature of LMR is the production of negative images with overhung profiles. Such profiles are attributed to LMR possessing a large absorbance in the deep UV region (12 μm−1at 250 nm), which is of great advantage to the lift‐off process in the fabrication of GaAs‐FET, surface acoustic wave (SAW) devices, and so on. Furthermore, because of the good thermal stability of LMR, it can liftoff hard metals such as Ni and Mo. In order to elucidate the phenomenon that deep UV irradiation retards the dissolution rate of LMR, a mechanistic study has been carried out. In both LMR and its analog lacking diazoquinone moiety, their molecular weights Increase upon deep UV irradiation, which suggests that crosslinking occurs in the base resin. This is supported by 13C NMR analyses of photochemical reaction products and by detection of radical species produced from the base resin. The photochemical reaction of the base resin is important to understand the overall lithographic performance

ISSN:0032-3888    

DOI:10.1002/pen.760261606

出版商:Society of Plastics Engineers    

年代:1986

数据来源: WILEY

摘要:

AbstractA second‐generation capped deep‐UV portable conformable masking system Is described. Two major improvements of this system are; (1) The replacement of the PMMA bottom layer with the PMMA‐MA‐MAN terpolymer which has a higher thermal stability and a higher deep‐UV sensitivity. (2) The application of the mold hardening process to eliminate the “wings” protruding from the novolac‐terpolymer interface, to facilitate a better choice of developers for the bottom layer, and to provide a better refractive index match between the novo

ISSN:0032-3888    

DOI:10.1002/pen.760261607

出版商:Society of Plastics Engineers    

年代:1986

数据来源: WILEY

摘要:

AbstractRadiation‐induced reactions of polystyrene derivatives have been studied by the radiolysis of ring‐substituted isopropylbenzene derivatives, i. e., 4‐amino. 4‐hydroxy, 4‐methoxy, 4‐methyl, 4‐chloromethyl, 4‐chloro, and 4‐acetyl derivatives. Low‐temperature ESR analyses measured at 77 K indicate that. In general, the a‐position is the most sensitive site to radiation and that thus a‐radicals are produced through a‐hydrogen removal. However, among these derivatives, the amino, acetyl, chloromethyl, and. chloro derivatives undergo different reactions from the other derivatives. A phCOCH3cleavage from the‐ acetyl derivative and NH cleavage from the amino derivative occur, and chlorine removal takes place from the chloro‐methyl and chloro derivatives. Final products detected by gas chromatography‐mass spectrometry indicate not only that radiation‐induced free radical recombination occurs. but also that if chlorine is produced by radiation, hydrogen abstraction by radiation‐induced chlorine takes place prior to the free radical recombination. The susceptibility of each derivative to hydrogen abstraction by radiation‐induced active chlorine increases, as the electron‐donation of ring‐substituents is increased. Based on the clarified reaction mechanism, the design of polystyrene derivatives as resist materials is discussed and two new types of resist systems are described. One is a new chloromethylstyrene based blend resist, which is formulated from poly(4‐meth‐oxystyrene) and poly(4‐chloromethylstyrene). The other is a new non‐swelling alkaline developable negative resist, which is formulated from pol

ISSN:0032-3888    

DOI:10.1002/pen.760261608

出版商:Society of Plastics Engineers    

年代:1986

数据来源: WILEY

摘要:

AbstractAlternating copolymers of sulfur dioxide and vinyltrimethylsilane (VTMS) and terpolymers with allyltrimethylsilane (ATMS) and 1‐butene have been synthesized by low‐temperature, free radical‐initiated polymerization. The co‐polymers with VTMS were soluble but hydrolytically unstable. Whereas the copolymer from ATMS was insoluble, terpolymers containing less than 75 mol‐percent ATMS (relative to butene) were soluble in a variety of organic solvents. Moreover, they were stable against hydrolysis and had good film forming properties. Their electron beam sensitivity was 1.5 °C/cm2at 20 keV. and their contrast was ∼2. The terpolymers have been used as a top imaging layer in a two‐layer resist system to transfer half‐micron features into a 1.2μm‐thick Novolac planarizing layer by oxygen reactive io

ISSN:0032-3888    

DOI:10.1002/pen.760261609

出版商:Society of Plastics Engineers    

年代:1986

数据来源: WILEY

摘要:

AbstractAll high molecular weight polysilane derivatives are characterized by a very strong electronic absorption in the‐UV spectral region. The position of this absorption and the molar extinction coefficients are functions of both the nature of the substituent and the molecular weight. In this regard, both the λmaxand the ϵsi‐siincrease rapidly at first with increased catenation and approach limiting values al around 100 to 150 monomer units. Irradiation of these polysilane derivatives leads predominantly to chain scission and molecular weight reduction although the scission ing/crosslinking ratio is dependent on the nature of the substituents. The mechanism of the photodegradation involves both the extrusion of substituted silylene fragments and the formation of silyl radicals. Lithographically, we have exercised the polysilanes in two configurations: (1) O2‐RlE etch resistant barriers in multilayer structures and, (2) thin imaginable layers for O2‐RIE image transfer. In each case, the stability of the silicon polymers to O2‐RIE conditions is due to the formation of a thin skin of oxide. In the case of the bilayer configurations, the images have been developed both by conventional wet development and by excimer laser ablation at either 308 or 248 nm prior to image transfer. Using either mode, we have been able to generate and transfer submicron images without difficulty. Finally, the strong optical absorption of the polysilanes, coupled with the observed bleaching upon irradiation, suggests potential as contrast enhancing materials. The contrast enhancement gained by the use of a polysilane layer has been modeled by computer simulation and demonstrated exp

ISSN:0032-3888    

DOI:10.1002/pen.760261610

出版商:Society of Plastics Engineers    

年代:1986

数据来源: WILEY

摘要:

AbstractSpun‐on contour coating properties are characterized for two absorptive undercoats, AUCs, and a contrast‐enhanced layer, CEM‐388. A low‐pass frequency filter contour modeling procedure is used to simulate the coating contours on a real silicon‐on‐sapphire epi‐island layout. The computed thickness variations are used to estimate the variation in optical densities of these spun‐on films on the topography. The variations in optical densities arc discussed in terms of the expected dimensional deviations introduced into the patterned resist layer. At the same spun‐on thickness, one absorptive undercoat offers improvement in dimensional control when compared to the other. Changes in the thickness of the CEM‐388 layer may also introduce significant dimensional deviations in the underlying positive resist layer. In, both cases the more conformal spun‐on contour coating properties produce im

ISSN:0032-3888    

DOI:10.1002/pen.760261611

出版商:Society of Plastics Engineers    

年代:1986

数据来源: WILEY