WCO Explanatory Notes reproduced for reference. © World Customs Organization. Verify against official WCO publication.
38.18 Chemical elements doped for use in electronics, in the form of discs, wafers or similar forms; chemical compounds doped for use in electronics. This heading covers : (1) The chemical elements of Chapter 28 (for example, silicon and selenium) doped with, for example, boron or phosphorus, generally in a proportion of the order of one part per million, provided they are in the form of discs, wafers or similar forms. When m forms unworked as drawn, or in the form of cylinders or rods, they are classified in Chapter 28. (2) Chemical compounds such as cadmium selenide and suI hide, indium arsenide, etc., containing certain additives (e.g., ermanium, iodine) genera y in a proportion of a few per cent, with a view to their use in e ectronics, whether in the form of cylmdders, rods, etc., or cut into discs, wafers or similar forms. f H The heading covers such crystals, polished or not, whether or not coated with a uniform epitaxial layer. Those more extensively worked (e.g., by selective diffusion) fall in heading 85.41 as semiconductor devices.
1.- This Chapter does not cover : (a) Separate chemically defined elements or compounds with the exception of the following : (1) Artificial graphite (heading 38.01); (2) Insecticides, rodenticides, fungicides, herbicides, anti-sprouting products and plant-growth regulators, disinfectants and similar products, put up as described in heading 38.08; (3) Products put up as charges for fire-extinguishers or put up in fire-extinguishing grenades (heading 38.13); (4) Certified reference materials specified in Note 2 below; (5) Products specified in Note 3 (a) or 3 (c) below; (b) Mixtures of chemicals with foodstuffs or other substances with nutritive value, of a kind used in the preparation of human foodstuffs (generally heading 21.06); (c) Products of heading 24.04; (d) Slag, ash and residues (including sludges, other than sewage sludge), containing metals, arsenic or their mixtures and meeting the requirements of Note 3 (a) or 3 (b) to Chapter 26 (heading 26.20); (e) Medicaments (heading 30.03 or 30.04); or (f) Spent catalysts of a kind used for the extraction of base metals or for the manufacture of chemical compounds of base metals (heading 26.20), spent catalysts of a kind used principally for the recovery of precious metal (heading 71.12) or catalysts consisting of metals or metal alloys in the form of, for example, finely divided powder or woven gauze (Section XIV or XV). 2.- (A) For the purpose of heading 38.22, the expression “certified reference materials” means reference materials which are accompanied by a certificate which indicates the values of the certified properties, the methods used to determine these values and the degree of certainty associated with each value and which are suitable for analytical, calibrating or referencing purposes. (B) With the exception of the products of Chapter 28 or 29, for the classification of certified reference materials, heading 38.22 shall take precedence over any other heading in the Nomenclature. 3.- Heading 38.24 includes the following goods which are not to be classified in any other heading of the Nomenclature : (a) Cultured crystals (other than optical elements) weighing not less than 2.5 g each, of magnesium oxide or of the halides of the alkali or alkaline-earth metals; (b) Fusel oil; Dippel's oil; (c) Ink removers put up in packings for retail sale; (d) Stencil correctors, other correcting fluids and correction tapes (other than those of heading 96.12), put up in packings for retail sale; and (e) Ceramic firing testers, fusible (for example, Seger cones). 4.- Throughout the Nomenclature, “municipal waste” means waste of a kind collected from households, hotels, restaurants, hospitals, shops, offices, etc., road and pavement sweepings, as well as construction and demolition waste. Municipal waste generally contains a large variety of materials such as plastics, rubber, wood, paper, textiles, glass, metals, food materials, broken furniture and other damaged or discarded articles. The term “municipal waste”, however, does not cover : (a) Individual materials or articles segregated from the waste, for example wastes of plastics, rubber, wood, paper, textiles, glass or metals, electrical and electronic waste and scrap (including spent batteries) which fall in their appropriate headings of the Nomenclature; (b) Industrial waste;