Tetrakis(tert-butoxy)hafnium — Hf(OtBu)₄

SAFC Hitech® Tetrakis(tert-butoxy)hafnium is available in a wide range of ultra-high purity grades and is supplied to customers worldwide through our network of local distribution facilities.

To accommodate the range of customer requirements, SAFC Hitech has invested in production and filling facilities capable of handling a wide variety of different containers, specializing in fill quantities between 25g and 25kg. Customer specific containers and fill requests can also be considered.

Hafnium t-butoxide
HFTBUT
Hf(OtBu)4
Hf(OC(CH3)3)4
Hf(OC4H9)4

Tetrakis(tert-butoxy)hafnium, Hf(OtBu)4, is used as a hafnium source for the deposition of HfO2 dielectric layers. Hafnium oxide is a leading candidate to replace silicon dioxide as the gate oxide in metal oxide semiconductor field effect transistors (MOSFET)[1]. The thin film properties which make HfO2 an attractive prospect for a gate oxide replacement also make it a potential insulating dielectric in the capacitive elements in memory devices such as DRAM[2]. Hf(OtBu)4 is primarily used in conventional CVD for the deposition of HfO2. However, Hf(OtBu)4 also deposits HfO2 via a variety of other techniques including plasma or UV assisted CVD, MOMBE and ALD[3,4,5]. Hf(OtBu)4 can also be used with a variety of other sources to deposit mixed alkoxides such as HfSiOx[6]. The volatility and thermal stability of the source is such that Hf(OtBu)4 can be transported from a bubbler in conventional CVD/ALD systems[7,8]. Additionally it can be used in liquid injection systems either neat or as a dilute solution. In all applications contamination is a key factor and research work at SAFC Hitech has been successful in developing purification routes to remove metallic and organic impurities. Product is certified according to the specification.

SAFC Hitech have installed the latest technologies in process equipment design and operational control to yield efficient and reliable production facilities for Tetrakis(tert-butoxy)hafnium. Multiple production locations and appropriate modular systems ensure an uninterrupted supply of Hf(OtBu)4 globally. SAFC Hitech is basic in Hf(OtBu)4 manufacturing with capabilities to produce high purity raw materials, control contamination sources and minimize impurity levels in the final product. Furthermore, SAFC Hitech employs specially developed purification processes for Hf(OtBu)4 that provide the lowest levels of metallic and hydrocarbon impurity levels on a consistent basis.

Tetrakis(tert-butoxy)hafnium is certified in-house using the latest analytical techniques, and film growth ensures the validity of the methods and that the Hf(OtBu)4 is capable of producing high quality films for state-of-the-art device fabrication.

SAFC Hitech employs the latest analytical techniques with ultra-low detection limits for all the potential contaminants in Tetrakis(tert-butoxy)hafnium. Hf(OtBu)4 is sampled and analyzed during and post manufacture to ensure the highest final product specification and reliability. The analysis is performed using a wide variety of physical characterisation techniques including ICP-OES, ICP-MS, NMR, TGA, vapour pressure, GC-AED and AA, on state-of-the-art tools specially upgraded for Hf(OtBu)4 impurity detection.

Considerable effort has been expended to develop suitable methodologies to provide accurate, reproducible data for the different grades of product available. As for many of its manufactured products, SAFC Hitech regularly reviews the analytical data it collects and can provide SPQ data to its customers.