Nitrate ferric

Ferric nitrate was among the first oxidizers used in early tungsten and copper CMP processes. As indicated in the Pourbaix diagram [25] for Fe (Fig. 7.8), the reduction potential is 0.77 V for Fe Fe reaction. Considering the fact that the reduction potential for Cu Cu is 0.52 V, ferric nitrate has more than adequate oxidizing power for the Cu CMP process (Eq. 7.7). 

Owing to the fact that free ferric ions are stable only in the acidic regime (Fig. 7.8), most slurries using ferric ions as an oxidizer are formulated at pH substantially below 4. At such a low pH, the copper surface oxidized via the reaction described in Equation 7.7 will not form any native oxide film. Without the protection from such an oxide, the copper surface is prone to corrode, which results in high static etch rate and practically no planarization efficiency. To provide a balance, therefore, the presence of a corrosion inhibitor is a must for copper CMP slurry. 

Babu and coworkers [26,27] investigated the copper dissolution in the presence of Fe using a copper rotating disk electrode (RDE). The cathodic reaction was separately studied using a platinum rotating disk electrode, while the overall corrosion process was measured on rotating disks. It was 

FIGURE 7.8 Pourbaix diagram of Fe-water system (from Ref. 25). 

Ferric nitrate has also been used widely as an oxidizer in W CMP slurries. As a matter of fact, ferric nitrate based slurry was successfully used for tungsten CMP applications long before its application to copper films. Unlike copper, however, tungsten does not usually require the use of inhibitors in the slurries. Tungsten is a much harder metal in comparison to copper. Under oxidizing condition, tungsten has much better passivation characteristics. More 

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The catalyst is finely-divided iron and is produced by adding a little crystallised ferric nitrate and a slight excess of sodium to liquid ammonia the reaction is probably ... 

TABLE 2-52 [Fe,(S04)3] Ferric Sulfate TABLE 2-53 [FeCNOala] Ferric Nitrate TABLE 2-58 Hydrogen Fluoride (HF) TABLE 2-59 Hydrogen Peroxide (H O ) ... 

Clay-supported ferric nitrate (Clayfen) or clay-supported cupric nitrate (Claycop), pentane, rt, 60-97% yield. ... 

Ferric nitrate (9H2O) [7782-61-8] M 404.0, m 47°(dec). Cryst from aqueous solutions of moderately strong HNO3 as the violet nonahydrate. With more concentrated aqueous solns (containing some HNO3), the hexahydrate crysts out. The anhydrous salt is slightly deliquescent and decomposes at 47°. 

If the reaction of potassium with liquid ammonia slows down before all the potassium is consumed, an additional pinch of ferric nitrate hydrate is added. 

In a 1-1. three-necked flask fitted with a motor stirrer (Note 1), gas inlet tube, dropping funnel, and a wide-bore soda-lime tube are placed 400-500 ml. of liquid ammonia and 0.1 g. of ferric nitrate nonahydrate (Note 2). 

Chemical Designations - Synonyms Ferric nitrate monahydrate, Nitric acid, iron (+3) salt Chemical Formula Fe(N03)3 9H20. 

The immediate outcome of the Hantzsch synthesis is the dihydropyridine which requires a subsequent oxidation step to generate the pyridine core. Classically, this has been accomplished with nitric acid. Alternative reagents include oxygen, sodium nitrite, ferric nitrate/cupric nitrate, bromine/sodium acetate, chromium trioxide, sulfur, potassium permanganate, chloranil, DDQ, Pd/C and DBU. More recently, ceric ammonium nitrate (CAN) has been found to be an efficient reagent to carry out this transformation. When 100 was treated with 2 equivalents of CAN in aqueous acetone, the reaction to 101 was complete in 10 minutes at room temperature and in excellent yield. 

Eisenozyd, n. iron oxide, specif, ferric oxide, iron(Ul) oxide. — salpetersaures —, ferric nitrate, iron(III) nitrate (and so for other salts). 

Ferri-hydroxyd, n. ferric hydroxide, iron(III) hydroxide, -ion, n. ferric ion, -jodat, n. ferric iodate. -jodid, n. ferric iodide, iron(III) iodide. -kalium3Ulfat, n. ferric potassium aulfate. -nitrat, n. ferric nitrate, iron(III)... 

Besides Fe-, other reducing agents that may be used in conjunction with H2O2 are aliphatic amines, Na2S203 thiourea, ascorbic acid, glyoxal, sulfuric acid, NaHSOs, sodium nitrite, ferric nitrate, peroxidase, AgNOs, tartaric acid, hydroxylamine, ethylene sulfate, sodium phosphite, formic acid, ferrous ammonium sulphate, acetic acid, ferrous sulphate, and HNO2, etc,... 

A suspension of sodium amide2 (0.1 mole) in liquid ammonia is prepared in a 500-ml. three-necked, round-bottomed flask fitted with a West condenser, a ball and socket glass mechanical stirrer (Note 1), and a dropping funnel. In the preparation of this reagent a small piece of clean sodium metal is added to 350 ml. of commercial anhydrous liquid ammonia. After the appearance of a blue color, a few crystals of hydrated ferric nitrate are added, whereupon the blue color is discharged. The remainder of the 2.3 g. (0.1 mole) of sodium (Note 2) is then rapidly added as small pieces. After all the sodium has been converted to sodium amide (Note 3), a solution of 16.4 g. (0.1 mole) of ethyl phenyl-acetate (Note 4) in 35 ml. of anhydrous ethyl ether is added dropwise over a 2-minute period, and the mixture is stirred for 20 minutes. To the dark green suspension is added over an 8-minute period a solution of 18.5 g. (0.1 mole) of (2-bromo-... 

Farnesol, 56,112 Ferric chloride, 57,17 Ferric nitrate, 57,66 Ferrocene, 56,28... 

Aluminium sulphate Ammonium bifluoride Ammonium bisulphite Ammonium bromide Ammonium persulphate Antimony trichloride Beryllium chloride Cadmium chloride Calcium hypochlorite Copper nitrate Copper sulphate Cupric chloride Cuprous chloride Ferric chloride Ferric nitrate... 

Eerrocene (1) was the first sandwich complex to be discovered, thereby opening a wide and competitive field of organometallic chemistry. The formation of ferrocene was found at almost the same time in two independent studies on July 11, 1951, Miller, Tebboth, and Tremaine reported that on the passage of N2 and cyclopenta-diene over a freshly prepared mixture of reduced Ee (90%), alumina (8%), potassium oxide (1%), and molybdenum oxide (1%) at 300°C, yellow crystals identified as Cp2Ee (Eig. 1) were obtained [1]. Due to the low yields obtained (3 g starting from 650 g ferric nitrate), doubts remain as to whether Ee(0) was the... 

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