摘要:

A proximity effect correction system has been developed by utilizing an efficient dose modulation technique based on a double Gaussian proximity function. A shaped electron beam system is assumed to be used. Two improvements are made. First, an optimal exposure dose on each pattern is determined by a new fast iterative method. The optimal dose makes the development isocontour conform to the pattern specification fairly well. Second, a ‘‘simple cell unit algorithm’’ that one of identical cells is proximity‐corrected, and the result is used to the other remaining cells is introduced. This offers to both decrease the processing time and save the memory/disk space. The present system is applied to the data processing of scaled‐down version of an aluminum wiring layer pattern of 16 Mbit dynamic random access memory with its minimum dimension of 0.4 μm. The calculation is successfully completed within 1 h of CPU time on a 10 MIPS general‐purpose computer. The dimensional accuracy of 10% is confirmed experimentally for the pattern including minimum features of 0.4 μm in the combination of trilayer resist process.

ISSN:1071-1023    

DOI:10.1116/1.586287

出版商:American Vacuum Society    

年代:1992

数据来源: AIP

摘要:

This work investigates electromigration (EM) in Al‐1 wt %Si, Al‐1 wt %Si‐0.5 wt % Cu and Al‐0.5 wt % Cu films with TiN barrier metals. The EM resistance of the Al‐0.5 wt % Cu layered metallization was found to be higher than that of the Al‐1 wt % Si‐0.5 wt % Cu layered metallization. The electromigration test results show that the reaction between Al films and underlying TiN layer degrades the electromigration performance of the Al‐1 wt % Si, Al‐1 wt % Si‐0.5 wt % Cu films. The reaction kinetics between Al alloys and TiN layers was studied by transmission electron microscopy and by investigating the resistance rise mechanism. Si was found to enhance thin intermetallic compound formation between the Al alloys and TiN on samples annealed at 450 °C.

ISSN:1071-1023    

DOI:10.1116/1.586288

出版商:American Vacuum Society    

年代:1992

数据来源: AIP

摘要:

Sputter deposited Cu films on top of a substrate were melted and recrystallized by irradiating under a XeCl (308 nm) excimer laser with a 45 ns pulse duration at substrate temperatures of 20, 365, and 440 °C. The properties of the irradiated film, such as sheet resistance, reflectance, grain size, stress, and preferred orientation were characterized as a function of the laser fluence at each of temperatures. The results show a decrease in sheet resistance and specular reflectance, and an increase in grain size after laser irradiation. The net stress of the film stack changes from compressive to tensile with substrate heating and laser irradiation and the polycrystalline orientation of the Cu films changes from (111) for the as‐deposited sample to (110) after laser irradiation. The significance of these results is discussed.

ISSN:1071-1023    

DOI:10.1116/1.586289

出版商:American Vacuum Society    

年代:1992

数据来源: AIP

摘要:

XeCl excimer laser (λ=308 nm) was used to melt and flow sputter deposited Cu film into contacts and trenches of different depths to fill them and to achieve a planarized surface. The process windows (in terms of laser fluence at substrate temperatures of 20, 365, and 440 °C) for the planarization and complete fill were investigated. We found that it is possible to completely fill the contacts and trenches of 1 μm in width and 1 μm in depth with an appreciable process window. However, we were only able to fill these 1 μm wide contacts and trenches of 2 μm in depth at 440 °C. The results and other phenomena will be discussed.

ISSN:1071-1023    

DOI:10.1116/1.586290

出版商:American Vacuum Society    

年代:1992

数据来源: AIP

摘要:

A rapid, inexpensive temperature measurement scheme, applicable across a broad temperature range, based on noncontact measurement of the expansion of a grating structure on the surface of interest is demonstrated. A simple projection moiré technique is used to remotely determine the grating periodicity and, hence, the temperature. An optical Fourier transform technique is introduced to simplify the analysis. A sensitivity of ±0.5 °C for a grating length of 6 mm in a Si wafer around room temperature is demonstrated.

ISSN:1071-1023    

DOI:10.1116/1.586291

出版商:American Vacuum Society    

年代:1992

数据来源: AIP

摘要:

Monolayer coverages of C60on a gold substrate have been studied using scanning tunneling microscopy. The images reveal various packing arrangements and reproducible intramolecular contrasts of the C60molecules. We find thatapproximatelyeveryothercarbonatomis highlighted on the π‐electron surface of the molecule as a result of a preferential electron transfer from the gold substrate, in agreement with a theoretical analysis of the high‐lying π‐electron density of a C60molecule adsorbed on metallic surfaces.

ISSN:1071-1023    

DOI:10.1116/1.586293

出版商:American Vacuum Society    

年代:1992

数据来源: AIP

摘要:

At room temperature, anisotropic etching of both (100) and (111) oriented single‐crystalline silicon substrates is successfully achieved, using a thermally excited ClF3molecular beam. The morphology of the etched surface is better than that using Cl2. The etching rate is more than 50 Å/min, and the ratio of etching rate of vertical direction to that of horizontal direction is more than eight. Process‐induced damage in the metal–oxide semiconductor device was not observed from the capacitance–voltage characteristic measurements.

ISSN:1071-1023    

DOI:10.1116/1.586294

出版商:American Vacuum Society    

年代:1992

数据来源: AIP

摘要:

A theoretical and experimental investigation into the formation of resist debris due to proximity exposure compensation (PEC) in electron beam lithography is provided. The two dimensional simulation of resist contours in closely spaced rectangular patterns shows that the unsupported resist fragments (debris) originate at the top of the resist when a PEC scheme based on dose variation method is used to compensate for the proximity exposure effects within and between the patterns. It is found that by taking some precautions during electron exposure and development process, the adverse effects of resist fragments can be eliminated.

ISSN:1071-1023    

DOI:10.1116/1.586295

出版商:American Vacuum Society    

年代:1992

数据来源: AIP

摘要:

A method for preparing cross sectional transmission electron microscopy (TEM) specimens using thin film processing techniques is described. Optical lithography is used to pattern lines of photoresist on the sample, followed by shadow evaporation of Al against the resist sidewalls. Removal of the resist leaves free standing, 100 nm wide metal lines on the surface. A selective, anisotropic reactive ion etch into the substrate then produces 1.5 μm tall, 100 μm wide walls, which, when turned on their sides, are sufficiently thin to allow transmission of high energy electrons in the TEM. This technique permits very specific, as well as very large, regions of a sample to be thinned for cross sectional examination. The processing steps are straightforward and may be easily adapted to other materials.

ISSN:1071-1023    

DOI:10.1116/1.586296

出版商:American Vacuum Society    

年代:1992

数据来源: AIP

ISSN:1071-1023    

DOI:10.1116/1.586297

出版商:American Vacuum Society    

年代:1992

数据来源: AIP