Trimethylgallium — TMGa

SAFC Hitech® Trimethylgallium 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.

TMG
TMGa
Ga(CH3)3
Me3Ga
(CH3)3Ga
Trimethylgallium

Trimethylgallium (TMGa) is the most widely used source for GaAs MOVPE. A room temperature (20°C) V.P. of 182 torr makes it suitable for both atmospheric and low pressure applications.

Early studies used TMGa with arsine to grow high quality GaAs (p = low-mid 1014cm-3 and µ77K > 120000cm2/Vs)[1,2]. Low temperature PL identified that carbon was the dominant residual shallow acceptor[1]. It is generally considered that carbon incorporation is enhanced by very low or very high growth temperatures, low V-III ratios and low pressure[3]. The limits of intrinsic carbon incorporation have been investigated with the growth of high purity GaAs (n = low 1013cm-3 and µ48K = 213000cm2/Vs)[4].

SAFC Hitech has pioneered the adduct purification of TMGa to ensure a guaranteed supply of high purity product, free from residual metal impurities and hydrocarbons[5,6]. Typical growth results using adduct purified TMGa with high purity arsine would be n < 1014cm-3 and µ77K = 110000cm2/Vs).

SAFC Hitech EpiPure™ TMG, with low silicon levels (less than 0.03ppm) and oxygen contamination (less than 1ppm) is particularly suitable for the growth of GaN where the high substrate temperatures typically used would lead to an enhanced incorporation of impurities.

SAFC Hitech has manufactured TMGa since 1985. During this time we have continued to incorporate and install the latest technologies in process equipment design and operational control to yield efficient and reliable plants that can run continuously. Built-in redundancy, modular design and multiple production locations ensure an uninterrupted supply of TMGa. SAFC Hitech has a simple, effective way of manufacturing TMGa from the basic raw materials ensuring impurity sources are at a minimum. Furthermore, SAFC Hitech employs specially developed purification processes for TMGa that yield the lowest levels of oxygen-containing species in the final product. The proven technique of adduct purification is also used to ensure the lowest levels of metallic and hydrocarbon impurities on a consistent basis.

TMGa is certified in-house using the latest analytical techniques, and periodic film growth ensures the validity of the methods and that the TMGa is capable of producing state-of-the-art device structures.

SAFC Hitech employs the latest analytical techniques with ultra-low detection limits for all the potential contaminants in TMGa.

TMGa is sampled and analysed 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 TMGa 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.