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In the microelectronics industry, a simple tape test (ASTM 3359) is typically used to qualitatively study the adhesion of dielectric films. In this work, a novel approach to conduct the tape test is proposed. This new method eliminates the inconsistency in the results encountered in the traditional tape test, and, at the same time, it provides both qualitative and quantitative results. This approach employs a spring-loaded mechanism and eliminates the subjective interpretation of the results of the traditional tape test. It also provides quantitative measures of the peel rate and force, factors that are relevant in the characterization of the interfacial strength of thin films. We illustrate the use of this new, modified tape test (MTT) in the study of the adhesion of multi-layered thin film structures. This study is of significance to the understanding of the damascene interconnect process integration. Thus, the adhesion of various films (e.g. oxide, insulator and metallic films) on the spun-on porous ca...

In this work, chemical vapor deposited low-k films using trimethylsilane (3MS) as the linear precursors and tetramethylcyclotetra siloxanes (TMCTS) as the cyclic precursors are studied. There are four processes studied: O 2 , O 2 + He process and CO 2 , CO 2 + O 2 process for 3MS and TMCTS precursors, respectively. Films deposited by the 3MS and TMCTS processes displayed similarities in the relationship between the Fourier transform infrared spectroscopy peak ratios, dielectric constants, refractive indexes, hardness, and modulus. The dielectric constant was found to have a linear relationship with hardness and modulus and inversely proportional with the Si-CH 3 /Si-O peak ratio for both precursors. It is believed that the introduction of a methyl group in the film has reduced the covalency of the Si-O bond thus reducing its dielectric constant in comparison with silica. In this work, the 3MS based low-k films appear to have slightly wider process windows compared to the TMCTS based low-k films. The linear precursors (3MS) in both O 2 + He and O 2 process and cyclic precursors (TMCTS) in both CO 2 + O 2 and CO 2 processes yielded similar hardness and modulus values for the same range of dielectric constants. In terms of the films electrical properties and stability, all films indicate mild stress where the 3MS system showed lower values of stress, good thermal stability, breakdown voltage, and leakage current values that are comparable to silica.

In this work, chemical vapor deposited carbon doped oxide films using trimethyl silane precursors with dielectric constant in the range of 2.75 to 3.62 were studied. Process parameters studied included low frequency RF (LFRF) and high frequency RF (HFRF) power, pressure, and helium flow rates as the oxidation influencing agents. Reliability and thermal stability of the films were studied and the dielectric constant (k), breakdown voltage, and leakage current were measured at 1 MHz. Numerous film properties (film stresses, hardness, modulus, refractive indices, and chemical bonding) were characterized. Results indicate that reduction of LFRF or HFRF power and the increase in pressure reduces the dielectric constant. Helium gases dissociate the Si–CH3 and C–H bond in the structure causing the dielectric constant to increase linearly as the helium flow rate increased while keeping the oxygen flow rate constant (O2+He process). It was observed that the O2 process window lowers the k value range and imparts sl...