Abstract: A method of detecting defects in a structure sample comprising a thin film layer and a sacrificial later is disclosed. The method comprises exposing the thin film layer to a vapour phase etchant, obtaining an image of the thin film layer and analysing the image. The vapour phase etchant enhances any defects present in the thin film layer by passing through the defect and etching a cavity within the sacrificial layer. The cavity undercuts the thin film layer resulting in a stress region surrounding the defect. Defects which were not originally detectable may be made detectable after exposure to the vapour phase etchant. A vapour phase etchant has the advantage of being highly mobile such that it can access defects that a liquid phase etchant might not. Furthermore, unlike a liquid phase etchant, a vapour phase etchant can be used to test a sample non-destructively.

Abstract: The etching of a sacrificial silicon dioxide (SiO2) portion in a microstructure such as a microelectro-mechanical structures (MEMS) by the use an etchant gas, namely hydrogen fluoride (HF) vapor is performed with greater selectivity to other portions within the MEMS, and in particular portions of silicon nitride (Si3N4). This is achieved by the addition of a secondary non-etchant gas suitable for increase the ratio of difluoride reactive species (HF2? and H2F2) to monofluoride reactive species (F?, and HF) within the HF vapor. The secondary non-etchant gas may comprise a hydrogen compound gas. The ratio of difluoride reactive species (HF2? and H2F2) to the monofluoride reactive species (F?, and HF) within the HF vapor can also be increased by setting an etch operating temperature to 20° C. or below.

Abstract: A method and an apparatus for etching microstructures and the like that provides improved selectivity to surrounding materials when etching silicon using xenon difluoride (XeF2). Etch selectivity is greatly enhanced with the addition of hydrogen to the process chamber.

Abstract: A method and an apparatus for etching microstructures and the like that provides improved selectivity to surrounding materials when etching silicon using xenon difluoride (XeF2). Etch selectivity is greatly enhanced with the addition of hydrogen to the process chamber.

Abstract: The present invention describes a deposition method suitable for depositing a coating on a device. The method is particularly suited for depositing a self assembled monolayer (SAM) coating on a micro electro-mechanical structures (MEMS). The method employs carrier gases in order to form a deposition vapour in a process chamber within which the device is located wherein the deposition vapour comprises controlled amounts of a vapour precursor material and a vapour reactant material. Employing the described technique avoids the problematic effects of particulate contamination of the device even when the volumetric ratio of the reactant material to the precursor material is significantly higher than those ratios previously employed in the art. The vapour precursor material can be of a type that provides the MEMS with an anti-stiction coating with the associated vapour reactant material comprising water.

Abstract: A controlled method of releasing a microstructure comprising a silicon oxide layer located between a substrate layer and a layer to be released from the silicon oxide layer is described. The method comprises the step of exposing the silicon oxide layer to a hydrogen fluoride vapor in a process chamber having controlled temperature and pressure conditions. A by-product of this reaction is water which also acts as a catalyst for the etching process. It is controlled employment of this inherent water source that results in a condensed fluid layer forming, and hence etching taking place, only on the exposed surfaces of the oxide layer. The described method therefore reduces the risk of the effects of capillary induced stiction within the etched microstructure and/or corrosion within the microstructure and the process chamber itself.

Abstract: The etching of a sacrificial silicon dioxide (SiO2) portion in a microstructure such as a microelectro-mechanical structures (MEMS) by the use an etchant gas, namely hydrogen fluoride (HF) vapour is performed with greater selectivity to other portions within the MEMS, and in particular portions of silicon nitride (Si3N4). This is achieved by the addition of a secondary non-etchant gas suitable for increase the ratio of difluoride reactive species (HF2? and H2F2) to monofluoride reactive species (F?, and HF) within the HF vapour. The secondary non-etchant gas may comprise a hydrogen compound gas. The ratio of difluoride reactive species (HF2? and H2F2) to the monofluoride reactive species (F?, and HF) within the HF vapour can also be increased by setting an etch operating temperature to 20° C. or below.