Metallized device and method of fabrication

#This invention relates to a metallized body of crystalline material and to a method of fabricating. More specifically, the present invention relates to a diamond material that has been metallized and to the method for metallization of a diamond material.

#In the past, it was difficult to metallize a crystalline diamond material so that the metallization would adhere to the material. In the prior art, sputtering techniques have been used for the metallization of crystalline material such as diamonds, but such techniques had several distinct disadvantages. Sputtering a metal onto a diamond surface, in the prior art, required the diamond being placed in an evacuated sputtering system in which the diamond was first sputter etched and then metallized. Both steps had to be performed consecutively in the evacuated sputtering system. The vacuum system could not be broken between process steps since to assure adhesion of the metal onto the diamond it is essential that the diamond surface be cleaned as a result of the sputter etching. In addition, since prior art metallization of a diamond material must be performed in a sealed sputtering system, the entire surface of the diamond is covered with a metallic layer, because it is not convenient to introduce a selective mask into the vacuum system to form a metallic pattern.

#A metallized diamond device including a body of diamond material having a layer of an oxide material on the surface of the body. Such a metallized diamond device can be fabricated by a method of metallizing a body of crystalline material in which simultaneously a crystalline body is cleaned and an oxide layer is formed on the cleaned body. The metallic layer can be patterned by masking using photoresist technology. If however, the metallic layer is etched so as to form a pattern, a portion of the diamond surface may be exposed to the ambient and any further metallization onto the exposed surface is not possible without again sputter-etching the diamond surface. Sputteretching the diamond a second time would remove all metallization initially formed on the diamond surface. Therefore, it would be most advantageous to have a method of metallizing a diamond in which metallization can be performed on the diamond after the diamond has been removed from the sputteretching chamber.

#FIG. 1 is a cross-sectional view of the metallized body of diamond material of the present invention.

#FIG. 2 is a cross-sectional view of an apparatus suitable for the operation of the method of the present invention.

#FIG. 3 is a cross-sectional view of the metallized body of diamond material of the present invention, having a patterned metallic layer.

#Referring to FIG. 1, a metallized device 10 consists of a body of diamond material 12 having an oxide layer 14 on a surface of the body 12. On the oxide layer 14 is a metallic layer 16. The oxide layer 14 is typically an oxide of silicon or aluminum, but silicon dioxide is preferred since it is used extensively in photoresist technology. The metallic layer 16 is typically gold with a layer of any good wetting agent, such as titanium or chromium, between the gold and the oxide layer 14, to assure adherence of the gold.

#Referring to FIG. 2, an apparatus suitable for carrying out the method of fabricating a metallized crystalline body such as the metallized device 10 is generally designated as 110. The apparatus 110 comprises a sputtering chamber 111 in which is a cathode plate 115 and an anode plate 118. The anode plate 118 is separated from and directly over the cathode plate 115. The plates 115 and 118 are typically of a metal such as brass. An oxide substrate 114 is placed on the cathode plate 115. Bodies of crystalline material 112, typically diamonds, are disposed onto the oxide substrate 114, between plates 115 and 118. The bodies of crystalline material 112 are the same as the body of crystalline material 12 in FIG. 1, and the oxide substrate 114 is of the same material as the oxide layer 14 in FIG. 1.

#After the crystalline bodies 112 have been disposed on the substrate 114, the sputtering chamber 111 is closed and sealed, so as to be impervious to the ambient. Next, the sputtering chamber 111 is evacuated, by a vacuum pump 120, to approximately 5 .times. 10.sup..sup.-6 mm Hg. After evacuation of the sputtering chamber 111, the chamber 111 is back filled from a source 122 of a heavy noble gas. Usually, of the noble gases that can be used in sputtering the inert gas argon is preferred since it is both inexpensive and efficient as compared to other noble gases.