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High resistivity and peeling have been problems with electroless copper layers preventing their use as a seed layer. Further, when copper is electroplated onto this seed layer, the resistivity is as high as 4.0 ⍀ cm, much higher than the 2.2 ⍀ cm value when plated on a physical vapor deposition ͑PVD͒ seed layer. This paper describes the deposition of low resistivity in copper conductive layer on the electroless-plating copper seed layer. The resistivity of the as-deposited layer decreases from 4.0 to 2.7 ⍀ cm as the grain size increases from 33 to 42 nm. The grain size and resistivity of the copper layer correlate with the stress in the copper conductive layer and in seed layers. The grain growth can be enhanced by reducing the stress in the copper seed layer. A low stress and highly ͑111͒ oriented seed layer can be deposited with nucleation control. Stress reduction can also be achieved by employing the agglomeration process for the seed layer. A resistivity of 2.2 ⍀ cm was attained in this conductive layer electroplated from copper hexafluorosilicate electrolytic solution on the low stress seed layer. This resistivity is comparable to the value obtained in a conventional electroplated copper layer on the PVD seed layer.

We identified two aliphatic formates, ( Z , Z )-8,11-heptadecadienyl formate and ( Z )-8-heptadecenyl formate in the opisthonotal gland secretions of an unidentified acarid species, namely Sancassania sp. Sasagawa. Both compounds were isolated using silica gel column chromatography and the structures were elucidated by 1 H-NMR and GC/FT-IR. Further information on the double bond positions was obtained by GC-MS analysis of the corresponding dimethyl disulfide derivatives. Based on the estimated structures of the two formates and using linoleic and oleic acids as the respective starting materials, a simple four-step synthesis was achieved via Barton decarboxylation as the key step. The aliphatic formates identified in acarids thus far are neryl formate (( Z )-3,7-dimethylocta-2,6-dienyl formate) and lardolure (1,3,5,7-tetramethyldecyl formate), and both have been reported to have pheromone functions. The biological function of the two formates isolated in this study is currently being investigated. Although we can speculate that the two compounds were biosynthesized from linoleic and oleic acid, there is a possibility that the synthetic processes featured a novel chain shortening and formic acid esterification mechanism.