Integration of device regions
The present disclosure relates to a method for creating regions of different device types on a substrate having different pitches. The method includes dividing a substrate into a first device type region and a second device type region. The method further includes forming a target etch layer on the substrate. The method further includes forming a bottom mandrel layer on the target etch layer. The method further includes forming a plurality of alternating first pillars of a top mandrel material and first trenches between the first pillars on the bottom mandrel layer in the first device type region. The plurality of first pillars has a first pitch. The method further includes forming a plurality of alternating second pillars of the top mandrel material and second trenches between the second pillars on the bottom mandrel layer in the second device type region. The plurality of second pillars has a second pitch. The method further includes depositing tone inversion material in the first trenches.
1. A method for creating regions of different device types on a substrate having different pitches, comprising:
dividing a substrate into a first device type region and a second device type region;
forming a target etch layer on the substrate;
forming a bottom mandrel layer on the target etch layer;
forming a plurality of alternating first pillars of a top mandrel material and first trenches between the first pillars on the bottom mandrel layer in the first device type region, the plurality of first pillars having a first pitch;
forming a plurality of alternating second pillars of the top mandrel material and second trenches between the second pillars on the bottom mandrel layer in the second device type region, the plurality of second pillars having a second pitch; and
depositing tone inversion material in the first trenches.
2. The method of claim 1 , further comprising forming spacers lining sidewalls of each of the plurality of second pillars in the second device region.
3. The method of claim 1 , further comprising depositing a litho-assist layer on each of the plurality of second pillars.
4. The method of claim 1 , further comprising conformally depositing an optical planarization layer over the second pillars and a top surface of the bottom mandrel layer in the second device type region.
5. The method of claim 1 , further comprising conformally depositing the tone inversion material over top surfaces of the plurality of first pillars and over an optical planarization layer overlying the plurality of second pillars.
6. The method of claim 5 , further comprising removing the tone inversion material from the top surfaces of the plurality of first pillars and over the optical planarization layer overlying the plurality of second pillars while leaving the tone inversion material in the first trenches.
7. The method of claim 6 , further comprising removing the plurality of first pillars while leaving the tone inversion material disposed on the bottom mandrel layer in the first device type region and removing the optical planarization layer overlying the plurality of second pillars and over the bottom mandrel layer in the second device type region.
8. The method of claim 1 , further comprising forming first spacers about each of the plurality of first pillars and second spacers about each of the plurality of second pillars to render the second pitch about half the first pitch.
9. The method of claim 8 , further comprising removing the plurality of first pillars and the plurality of second pillars selective to the first spacers, the second spacers, and the bottom mandrel layer.
10. The method of claim 8 , further comprising:
removing the bottom mandrel layer selective to the first spacers and the second spacers, wherein bottom mandrel portions remain underlying the first spacers and the second spacers to form first bottom mandrel pillars and second bottom mandrel pillars, respectively;
forming third spacers along sidewalls of the first bottom mandrel pillars and forming fourth spacers about the second bottom mandrel pillars;
removing the first bottom mandrel pillars and the second bottom mandrel pillars to leave third spacer pillars in the first device region and second spacer pillars in the second device region; and
performing a pattern transfer through the target etch layer to form a first plurality of fins in the first device type region and a second plurality of fins in the second device type region to render the second pitch about one quarter of the first pitch.