Pattern formation in the fabrication of microelectronic devices

摘要

An all-dry microlithography process, where a fluorinated layer <Bold>30</Bold> is deposited on a processable layer <Bold>18</Bold> of a semiconductor wafer, and regions of the fluorinated layer <Bold>30</Bold> are exposed to a masked radiation source so that exposed regions and unexposed areas <Bold>31</Bold> are formed in the fluorinated layer <Bold>30</Bold>. An oxide layer is grown on the fluorinated layer, forming thicker region <Bold>34</Bold> of oxide on the unexposed areas <Bold>31</Bold> of the fluorinated layer <Bold>30</Bold>, and forming thinner regions <Bold>32</Bold> of oxide on the exposed regions of the fluorinated layer <Bold>30</Bold>. The oxide layer is then etched, removing thinner regions <Bold>32</Bold> of the oxide layer but leaving at least a fraction of the thicker portions <Bold>34</Bold> of the oxide layer to be used as a patterned hard mask. Then the exposed fluorinated layer not covered by the patterned oxide hard mask, is etched, to expose areas of the processable layer <Bold>18</Bold> not covered by the oxide hard mask, for subsequent patterned processing. The subsequent patterned processing may be an etch process for pattern transfer to the processable layer, a doping process to dope the exposed regions of the processable layer, or another process such as a deposition step.

The all-dry lithography process can be completed in an integrated environment, such as a cluster tool, resulting in improved manufacturing cycle time and increased yields. The dry photosensitive layer may be deposited using PECVD at low temperatures, and is compatible with all other semiconductor device fabrication process flows.