| 摘要 |
<p>The dimensions of mask patterns, such as pitch-multiplied spacers, are controlled by controlled growth of features in the patterns after they are formed. A pattern of mandrels is formed overlying a semiconductor substrate. Spacers are then formed on sidewalls of the mandrels by depositing a blanket layer of material over the mandrels and preferentially removing spacer material from horizontal surfaces. The mandrels are selectively removed, leaving behind a pattern of freestanding spacers. The spacers comprise a material, such as polysilicon and amorphous silicon, known to increase in size upon being oxidized. The spacers are oxidized and grown to a desired width. The spacers can then be used as a mask to pattern underlying layers and the substrate. Advantageously, because the spacers are grown by oxidation, thinner blanket layers can be deposited over the mandrels, allowing the deposition of more conformal blanket layers and widening the process window for spacer formation.</p> |
