Semiconductor Chemicals: Types, Standards & Applications

Semiconductor chemicals (semiconductor-grade chemicals) are extremely high-purity chemicals used to make integrated circuits, electronic chips, sensors and displays. Unlike ordinary industrial chemicals, even trace-level particles and metal ions in a semiconductor chemical can cause defects in circuits on a silicon wafer. This article classifies the main groups of semiconductor chemicals, explains the SEMI standard and how each production step uses them, and lists the products Lộc Thiên supplies to the Vietnamese electronics industry.

What are semiconductor chemicals?

Semiconductor chemicals are liquid or gaseous compounds of very high purity, used in the steps of making semiconductor devices: cleaning the silicon wafer surface, etching circuits, patterning by photolithography, doping and chemical vapor deposition (CVD). Transistor density on a modern chip is extremely high — a single dust particle or a trace-level metal ion can cause a short circuit and ruin the chip.

Common semiconductor chemicals:

SEMI purity standard

SEMI (Semiconductor Equipment and Materials International) publishes the C-series standards for liquid chemicals. Each chemical has its own standard — for example C27 for HCl, C28 for HF, C30 for H₂O₂, C35 for HNO₃ and C44 for H₂SO₄ — and is divided into Grades 1–5.

The higher the grade, the tighter the limits on metal impurities and particles, for smaller manufacturing nodes. The exact limits differ by chemical and by edition of the standard, so check the SEMI standard for the chemical in question (the general analysis guide is SEMI C1). A manufacturer declares that a product meets SEMI after testing with analytical methods validated under C1; SEMI does not “certify” products.

Lộc Thiên’s range contains no SEMI-grade chemicals at all (Grade 1–5); this section only helps you understand how the industry grades purity.

Photolithography

Photolithography is the step that transfers the circuit pattern onto the silicon wafer with UV light. Process: coat a light-sensitive photoresist → expose to UV through a mask → develop: a developer solution dissolves the photoresist that was exposed (for positive resist; with negative resist it is the opposite and the unexposed part dissolves) → uncover the silicon to be etched.

Key chemicals:

• Photoresist: light-sensitive polymer (positive or negative)
• Developer (TMAH — tetramethylammonium hydroxide): dissolves the exposed photoresist (positive resist). Concentration 2.38%
• Edge bead remover: removes excess photoresist at the wafer edge

Etching

After photolithography, the exposed silicon is etched to form trenches, via holes or 3D structures.

Wet etching: liquid chemicals remove the unwanted material.

Dry etching: plasma of gases (CF₄, SF₆, Cl₂) bombards the surface — more precise than wet etching, used for technologies below 90 nm.

Lộc Thiên supplies FeCl3 40% for copper etching of PCBs (an imported product from India), plus HCl 32% and HNO₃ 68% for plating and metal etching applications. See: FeCl3 for PCB — comparing 4 copper etchants.

Cleaning the wafer

Before every step, the silicon wafer must be cleaned absolutely — removing dust, oils, metal ions and the native oxide layer.

RCA clean (the industry-standard process):

Purity grade for cleaning: in chip manufacturing, the HCl, H₂O₂ and NH₄OH used in RCA cleaning must be electronic-grade chemicals that meet the relevant SEMI standard. Ordinary industrial chemicals are not used for this step.

Doping and CVD

Doping: introducing impurities into silicon to create n-type (P, As) or p-type (B) semiconductors. Source chemicals: POCl₃ (phosphorus oxychloride), BBr₃ (boron tribromide), AsH₃ (arsine gas).

CVD (chemical vapor deposition): depositing thin films of SiO₂, Si₃N₄ and polysilicon from the gas phase. Source chemicals: SiH₄ (silane), NH₃ (ammonia), WF₆ (tungsten hexafluoride), TEOS (tetraethyl orthosilicate).

CVD chemicals need very high (electronic-grade) purity because they directly affect the quality of the semiconductor film.

Products Lộc Thiên supplies

Lộc Thiên has no SEMI-grade chemicals. Lộc Thiên is a supplier of basic bulk industrial chemicals for PCB, electronic components and factory lab/QC use in Vietnam:

• HCl 32% (CAS 7647-01-0) — rust removal, plating, metal etching, pH adjustment
• HNO₃ 68% (CAS 7697-37-2) — copper etching/pickling, stainless-steel passivation
• H₂SO₄ 98% (CAS 7664-93-9) — plating, metal surface treatment, copper micro-etch solutions in PCB
• H₂O₂ 50% (CAS 7722-84-1) — oxidation, copper micro-etch solutions in PCB
• FeCl₃ 40% (CAS 7705-08-0) — PCB copper etching (imported from India)

The MSDS comes with the quotation; a test result sheet/COA depends on the product and is confirmed at quotation. PCB-line FeCl₃ is an imported product from India. Delivery: within HCMC in 4 hours; southern and Mekong Delta industrial parks in 24–48 hours; northern and central Vietnam in 2–3 days. Call 0979 891 929 — quotation in 15 minutes.

🛒 Need industrial chemicals for PCB and electronics? Quote for FeCl3 40% PCB Etching Grade — MSDS with the quotation, delivery within HCMC in 4 hours and southern industrial parks in 24–48 hours or Quote for HCl 32%–35% for rust removal, plating and metal etching. Quotation within 15 minutes.

Explore in depth: semiconductor and electronics chemicals

This hub links to the in-depth articles on chemicals for the electronics and semiconductor industries at Hóa Chất Lộc Thiên.

🧪 Main chemicals

• Hydrochloric acid HCl in full — CAS 7647-01-0 — rust removal, plating, metal etching
• Sulfuric acid H2SO4 in full — 98%, 75%, 50% — plating, metal surface treatment
• FeCl3 for PCB — comparing 4 copper etchants — PCB copper etching
• FeCl3 40% PCB Etching Grade (imported from India) — PCB copper etching

💡 Background knowledge

• What are electronic industrial chemicals? PCB, displays, batteries — an industry-by-industry overview: PCB/SMT, displays, batteries, telecom

Frequently asked questions

How do semiconductor chemicals differ from ordinary industrial chemicals?

Semiconductor chemicals are far purer than ordinary industrial chemicals: metal impurities are held to extremely low trace levels set by each SEMI grade. Even a small amount of metal impurity can destroy a circuit. Ordinary industrial chemicals typically carry Fe and Cu impurities at the ppm level.

How is FeCl3 used to etch PCBs?

FeCl3 at 36–40% and 40–50°C dissolves copper by the reaction Cu + 2FeCl₃ → CuCl₂ + 2FeCl₂. Etching takes 5–15 minutes depending on the copper thickness. Advantages: low cost and easy control. See comparing 4 copper etchants.

Does Lộc Thiên supply SEMI-grade chemicals?

No. Lộc Thiên supplies basic industrial chemicals for PCB, electronic components and factory lab/QC use. SEMI-grade chemicals (ppb/ppt) are not in the range, and Lộc Thiên does not publish a SEMI certificate for any product. If you need SEMI grade, contact Lộc Thiên to discuss the specific requirement before ordering.

What is Piranha solution?

Piranha solution is a mixture of H₂SO₄ 98% : H₂O₂ 30% (ratio 3:1), used to remove photoresist and stubborn organic contamination from wafers. The reaction temperature is 120–150°C; it is extremely corrosive and dangerous — use only in a cleanroom with full PPE.

Where can I buy chemicals for PCB production?

Lộc Thiên supplies FeCl3 40% (imported from India), HCl 32%, HNO₃ 68% and H₂SO₄ 98% for PCB and electronic component production. The MSDS comes with the quotation; a test result sheet/COA depends on the product and is confirmed at quotation. Delivery: within HCMC in 4 hours; southern and Mekong Delta industrial parks in 24–48 hours; northern and central Vietnam in 2–3 days.

Company information

CÔNG TY TNHH ĐẦU TƯ PHÁT TRIỂN LỘC THIÊN — Tax code 0313650856

452/6B Tỉnh Lộ 10, Bình Trị Đông Ward, Ho Chi Minh City · ☎ 0979 891 929 · hoachatlocthien.com

📖 Related articles (more on semiconductor / electronics chemicals):

• What is ammonium bifluoride NH4HF2? What you need to know