Tunable nanomasks for pattern transfer and nanocluster array formation

DETAILED DESCRIPTION It should be noted that all references cited in this Detailed Description are incorporated herein by reference, in their entirety.
In accordance with the present invention, we have used new methods of nanofabrication to produce ordered arrays of holes having diameters in the range of about 1 to about 30 nm and ordered arrays of single nanoclusters having diameters of about 5 nm.
These nanoclusters can be produced via a highly scaleable method for the inexpensive, parallel fabrication of dense, ordered arrays of semiconductor quantum dots that can serve in single layers as the emissive elements in active layers of electroluminescent devices, such as flat panel displays, ultrathin displays deployed on flexible substrates, and vertical-cavity surface-emitting lasers (VCSELs).
The dots or holes within an array have a highly uniform size and spacing, arising naturally from the inherent order of the nanometer-scale masks employed to create the quantum dots.
The formation of the dot arrays can proceed in a very straightforward way using a highly selective dry etching process followed by conventional molecular beam epitaxy.
Moreover, the technique does not require a strain field or complex growth kinetics as are often employed in multilayer quantum dot designs for VCSELs.
The combination of nanofabrication process steps is shown schematically in FIG.
1.
The steps include obtaining a mask 2 comprising a material 4, having a regular array of pores 6; mounting the mask 2 on a substrate surface 8; forming a thin metal or metal oxide layer 10 on the mounted mask 2; and pattern transfer onto the substrate surface 8 by low damage etching.
Nanoclusters, such as quantum dots, can be grown on the patterned substrate by adatom as deposition.
This method has collectively achieved massively parallel processing in fabricating an ordered and precisely positioned array of nanoclusters.
Alternatively, pattern transfer onto the substrate could occur by adatom deposition, without the etching step