Tetramethylammonium Hydroxide (TMAH)

Tetramethylammonium Hydroxide (TMAH) is a colorless liquid with a strong ammonia-like odor. It is soluble in water, and corrosive to metals and tissue.

TMAH is used to produce tetramethyl-ammonium azide. It is used as an anisotropic etchant of silicon, basic solvent in the development of acidic photoresist in photolithography process, as surfactant in the synthesis of ferrofluid and as a polarographic reagent. It finds application in the production of organic silicon, where it is used for computer silicon wafer surface brightener and cleaning agent. It is also involved in the purification of some metallic elements.

Technical Specifications

Package & Storage

• Net weight 200kg drum or 1000kg IBC drum.
• Store in tightly sealed container, protect from light.

Key Benefits & Advantages of Tetramethylammonium Hydroxide (TMAH)

Metal-Ion Free Strong Base:
TMAH is an organic quaternary ammonium compound that contains no alkali metal ions. This inherent characteristic eliminates the risk of metallic contamination that could cause electrical circuit failure or degrade sensitive electronic components. In semiconductor manufacturing, where even trace amounts of metallic contamination can lead to device failure, the metal‑free nature of TMAH directly translates to higher yields and more reliable products.

Residue‑Free Thermal Decomposition:
Upon heating to elevated temperatures, TMAH undergoes complete thermal decomposition into volatile gaseous products without leaving any solid residue. This clean decomposition profile eliminates the need for post‑process cleaning steps in many applications and prevents the accumulation of contaminants that could impair equipment performance or product quality. The decomposition pathway produces primarily methanol and trimethylamine, both of which are readily removed from processing chambers.

Excellent Solubility and Versatility:
TMAH is fully miscible with water and polar organic solvents, offering exceptional formulation flexibility. Its strong basicity makes it effective as a base solvent in acidic photoresist development, as a surfactant to prevent nanoparticle aggregation, and as a phase‑transfer catalyst enabling reactions between immiscible aqueous and organic phases. This combination of properties allows TMAH to serve multiple roles-developer, etchant, cleaner, catalyst, and formulation component-across a diverse range of industries.

Applications of Tetramethylammonium Hydroxide (TMAH)

TMAH is an important organic base compound with wide applications. The following are its main uses:

Semiconductor Manufacturing

• Photolithography developer: In the photolithography process of chip manufacturing, TMAH solution is used to develop the exposed photoresist, selectively dissolving the photoresist in the exposed area to form precise circuit patterns. It is an indispensable developer in advanced processes.
• Silicon wafer etchant: As an anisotropic wet etchant, TMAH can selectively etch different crystal planes of silicon and is used to fabricate micro-three-dimensional structures in micro-electromechanical systems (MEMS), such as grooves and pyramids. Moreover, as it does not contain metal ions, it will not contaminate the chips.
• Cleaning agent: It is used to clean the residual photoresist, organic contaminants, etc. on the surface of the wafer. It can gently remove impurities without corroding the metal interconnections or dielectric layers.

Display Panel Manufacturing

• In the manufacturing of display panels such as liquid crystal displays (LCDS) and organic light-emitting diodes (OLeds), TMAH is used in photolithography development and cleaning processes to ensure the accuracy of pixel patterns and display uniformity. Especially in flexible screens and micro-LED displays, its sub-nanometer control capability is of vital importance.

Chemical Synthesis

• Phase transfer catalyst: In organic synthesis, TMAH can serve as a phase transfer catalyst to promote the reaction between the aqueous phase and the organic phase, enhancing reaction efficiency and product purity. It is commonly used in the synthesis of organosilicon, rubber antioxidants, drug intermediates, etc.
• Complexing agent: It can form stable complexes with metal ions and is used in the preparation of catalysts, dyes, coatings, etc.

Analytical Chemistry

• As a polarographic analysis reagent, it is used to support electrolytes or methylation reagents, enhance the volatility of samples and detection sensitivity, and is suitable for trace component analysis.

Material Preparation

• In the synthesis of nanomaterials, by regulating the pH value and coordination environment of the reaction system, precise control of material size and morphology can be achieved, which is applicable to the preparation of nanomaterials such as oxides and metals.

Frequently Asked Questions (FAQs)

Q: What are the main applications of TMAH?
A: TMAH has four primary application areas: (1) Semiconductor manufacturing: photoresist developer, anisotropic silicon etchant, photoresist stripper, and cleaning agent; (2) Organic synthesis: strong base, phase‑transfer catalyst, and methylation reagent; (3) Analytical chemistry: chromatography reagent and pyrolysis‑GC/MS derivatization agent; and (4) Pharmaceutical & biotech: API synthesis, cell culture buffer, and laboratory reagent. It is also used in display panel production, photovoltaic texturing, and materials science applications.

Q: What are the advantages of using TMAH over inorganic bases like KOH?
A: TMAH offers three key advantages over inorganic bases: (1) Metal‑ion free: contains no alkali metal ions (Na⁺, K⁺) that could cause electrical circuit failure; (2) High anisotropic selectivity: provides superior etching anisotropy compared to KOH; and (3) Residue‑free decomposition: thermally decomposes into volatile gases without leaving solid residue, eliminating post‑process contamination concerns.

Q: How should TMAH solutions be stored safely? What is the shelf life?
A: Store in cool, dry, well‑ventilated area, protected from light. Keep away from acids, oxidizers, and heat sources.

Contact Us

For price, TDS, SDS or related products, please contact us at:

Email: [email protected]
WhatsApp: 86-18452425579