An oxygen-compatible radiant substrate heater for thin film growth at substrate temperatures up to 1050 °C

Abstract

A new radiative heater for high T c thin film growth Rev.The design and performance of a radiative substrate heater that operates under vacuum in a highly oxidizing environment is described. Using this heater, substrate temperatures exceeding 1050°C are readily achieved. These are the highest temperatures reported for a pulsed laser deposition ͑PLD͒ heater that operates in an oxidizing ambient. This heater was designed for the growth of oxide thin films by PLD, but the design concept is suitable for other vacuum deposition methods requiring high substrate temperatures to be achieved in an oxidizing environment. In addition to the high substrate temperatures achievable, the design described enables easy switching between on-axis PLD and off-axis PLD ͑allowing both sides of the wafer to be coated in the same growth͒ and allows the target-to-substrate distance to be easily adjusted from outside the chamber.

High-temperature goniometer for thin film growth and ion scattering studies

“…7 Radiative heaters, such as halogen lamps, would require a very large goniometer and water cooling at the sample stage. The above-mentioned problems can be avoided by using laser heating.…”

Versatile and economical specimen heater for ultrahigh vacuum applications

“…Substrate heaters on many commercial systems are based on radiative heat transfer processes which transfer heat to the substrate by infrared radiation. [24][25][26][27][28][29][30] Cillessen, de Jong, and Croize 31 have built a quartz halogen heater with a rotating absorber made of SiC for pulsed laser deposition applications. 18 This has the advantage of not breaking electrical contact when taking the holder out of the vacuum system, but most of the substrates of choice are transparent to visible light and poor absorbers of infrared radiation.…”

Synthesis of the superlattice complex oxide Sr5Bi4Ti8O27 and its band gap behavior

“…Phase purity was confirmed and the microstructure characterized by x-ray diffraction (XRD) and transmission electron microscopy (TEM), as well as confirming that the film was fully dense and epitaxial. The complex dielectric function (e ¼ e 1 þ ie 2 ) spectra, the resulting optical band gap behavior of the material, film thickness, and surface roughness layer thickness were measured by Thin films were grown in a radiatively heated PLD chamber, 25 which limits thermal variations across the surface of the substrate. PLD targets were prepared by milling highpurity powders of Bi 2 O 3 , TiO 2 , and SrCO 3 of at least 99.99% purity and sintering in air, adding 15% excess bismuth oxide to provide an overpressure of bismuth during PLD growth from the single target.…”

“…Film growths were performed by 10 000 pulses of a KrF excimer laser (k ¼ 248 nm) at 10 pulses/s and a fluence of 2-6 J/cm 2 onto SrTiO 3 (001) substrates at temperatures from 750-780 C 6 0.1 C (precision of readout as measured by a type N thermocouple) under 90 mTorr of molecular oxygen using a pseudo-blackbody substrate heater. 25 Films were quenched immediately after growth to avoid bismuth sub-oxide volatilization, which has been shown to lead to microstructural degradation in the absence of quenching. 26 Phase purity was studied by XRD, and was confirmed by TEM on a focused ion beam (FIB)-prepared lamella (FEI Nova 600) using an FEI Titan microscope operated at 300 keV.…”