Specific Process Knowledge/Thin film deposition/ALD Picosun R200/ZnO deposition using ALD

From LabAdviser

The ALD window for deposition of zinc oxide (ZnO) ranges from 100 oC to 250 oC. Several investigation techniques has been implemented for ZnO characterization. Additionally, more information on ZnO can be found on a page about Al-doped ZnO (AZO)

All results shown on this page have been obtained using the "ZnOT" recipe on new Si(100) wafers with native oxide:

ZnO standard recipe

Recipe: ZnOT

Maximum deposition thickness: 100 nm

Temperature: 100 oC - 250 oC

DEZ* DEZ H2O H2O
Nitrogen flow 150 sccm 150 sccm 200 sccm 200 sccm
Pulse time 0.1 s 0.1 s 0.1 s 0.1 s
Purge time 0.5 s 20.0 s 0.5 s 20.0 s

DEZ is diethylzinc (Zn(CH2CH3)2 or ZnEt2)

ZnO deposition rates and uniformity

The deposition rate for ZnO depends on the temperature, see the ALD-window graph below. The uniformity, thickness, refractive index has been obtained using Ellipsometer VASE.



Evgeniy Shkondin, DTU Danchip, 2014-2016.

ZnO XPS investigation for elemental trace analysis and deposition on high aspect ratio structures

XPS profile for ZnO has been obtained using XPS-ThermoScientific. ZnO samples reveals (see Figure 3a) chemically high quality films with no observable contaminations in temperature range 100 - 250 oC.

The recipe is good for deposition on very high aspect ratio structures (with aspect ratio more than 1:20) such as deep trenches, pillars, pores etc. ZnOT can also be used for deposition on polymers at low temperatures (80-120 oC).



Evgeniy Shkondin, DTU Danchip, 2014-2016.