The polarization of interdigitated gold electrodes mounted over a silica thin film formed by oxidation of a Si wafer produces reproducible electrostatic patterns with overall excess negative charge,as observed by scanning electric potential microscopy.Domain charge concentrations as high as 76 charge units per square micrometer are obtained when a 5 V difference is applied to the electrodes thus producing fields in the 10~6 V m~(-1) range.These patterns vanish when the electrodes are short-circuited and grounded.Characteristic times for pattern formation and relaxation are in the order of 10 min.The results are consistent with a model based on the discharge of H~+ ions at the negative electrodes,leaving behind immobile surface-bound SiO~- groups and thus showing that chemisorption phenomena are decisive for electrostatic charging of insulators.
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机译：通过扫描电势显微镜观察，安装在由Si晶片氧化形成的二氧化硅薄膜上的叉指式金电极的极化会产生可复制的静电图案，并带有整体过量的负电荷。最高电荷浓度为每平方微米76个电荷单位当在电极上施加5 V的电压差时会产生10〜6 V m〜（-1）的电场，当电极短路和接地时这些图案消失，图案形成和松弛的特征时间为大约10分钟。结果与基于负极上H〜+离子放电，留下固定的表面结合的SiO〜-基团的模型相一致的结果，因此表明化学吸附现象对于绝缘子的静电荷起决定性作用。
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