JPS63198316A - Tray for processing silicon wafer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION BACKGROUND OF THE INVENTION In the thermal processing of semiconductor components, such as silicon chips, one step in the processing is to provide the chip with a coating of specific thickness and characteristics. All processing of silicon chips is tightly controlled to exacting specifications. It is necessary that the chips are heated uniformly and that harmful substances do not contaminate them. Traditionally, to meet these standards, thermal processing is performed on trays made from alloys such as: The alloy meets US Federal Specification QQW390 and contains approximately 14-17% chromium, approximately 6-10% iron, and 1% manganese by weight.
Up to 0.5% silicon, up to 0.5% copper, up to 0.5% sulfur.
Inconel (lNC0NEL®) Alloy 60 is manufactured by Inco Alloys International and contains up to 15% nickel, with the remainder consisting essentially of nickel.
It is sold as 0. These trays are pre-oxidized to form a dark sticky oxide film. This dark adhesive oxide coating allows uniform heating of the chip in a radiant furnace while eliminating chip contamination. The dark adhesive oxide film and the substrate alloy are exposed to dilute hydrofluoric acid (aqueous HF) used to clean the trays after they are used to process silicon wafers.
It is also resistant to the action of

However, it has been found that this alloy, which meets US Federal Specification QQW390, will warp after being exposed to relatively few thermal processing cycles when formed into chip trays. Such distortion tends to create a gap between the tray and the chips placed thereon, which creates non-uniform chip heating. When this happens, the tray must be thrown away.

SUMMARY OF THE INVENTION The present invention contains a minimum of about 70% nickel and about 0.0% carbon by weight.
Up to 2%, iron approx. 0. 1 to about 20%, silicon about 0.05
- about 0.8%, about 10 to about 23% chromium, about 0.2 to about 1.5% aluminum, about 1.5 to about 3% titanium, about 0.1 to about 51 to about 51% of niobium and tantalum 3%, up to 0.2% zirconium and up to about 0.03% boron, with a total of about 2 to about 4% aluminum, titanium and silicon.
．． To provide a silicon chip heating tray containing an alloy of 5%, characterized in that the alloy surface of the tray is coated with a radioactive oxide film insoluble in hydrofluoric acid. It is intended for some purpose.

Preferred Embodiments of the Invention When using the silicon chip processing tray of the present invention,
It is advantageous to make the tray from an alloy within the composition range given in Table 1.

7,・' , / /'7・' Table 1 Carbon Maximum 0. [18 & large 0.08 manganese maximum 1.0 maximum 1.0 iron
5-9 5-9 sulfur
Maximum 0.01 Maximum 0601 Silicon Maximum 0.5 Maximum 0.5 Copper
Maximum 0.5 Maximum 0.5 chrome
14-17 14-17 Aluminum 0.4-1.0 0.9-1.5 Titanium
2.25-2.75 2.0-2.6 Niobium and tantalum 0.7-1.2 0.7-1.2 Nickel: Balance 70 Balance 70 Table■
Within alloy ranges such as those described in , and within the broader alloy range described above, manganese, copper, cobalt (included in nickel) are incidental elements. Sulfur, phosphorus, arsenic, selenium, tin, antimony, bismuth, etc. are considered impurities and should be kept at minimum practical amounts. Small amounts of zirconium (eg, up to about 0.1%), alone or with small amounts of boron (eg, 0.03%), can be incorporated into the alloy for various purposes, including increasing ductility.

An example of the silicon chip processing tray of the present invention is shown in the drawing, and will be explained based on this drawing. The plan view in Figure 1 is
Figure 1 shows the surface 11 of a rectangular tray having a length of at least about 460 mm and a width of at least about 200 m+* made of metal about L 3 mm thick. A plurality of tabs 13 extend from opposite ends of the tray surface 11 to provide a means for engaging a tray moving device in a radiant heating electric furnace. The vertical edge 15 is
Lip 1 that is folded back and extends downward as shown in FIG.
7 is formed. FIG. 2 is a cross-sectional view taken along a cross section (■-■) passing through two dimples 19. FIG. 3 is an enlarged view, and as shown, the surface 11 is made of metal 231+
, : has an oxide film 21 that is superimposed and fixed. It is important that the tray surface 11, apart from the dimples 19 and embossed stiffening ribs 20, is flat and remains flat through repeated thermal cycling.

Furthermore, the oxide film 21 is permanently adhered to the metal 23 and has such properties and thickness that it is a good absorber and radiator of heat and is resistant to the action of hydrofluoric acid. It is important to have

In making the silicon chip trays of the present invention, any one of the alloys in Table I, or any alloy within the broad alloy range described above, can be manufactured in sheet or strip form approximately 1.27 ml thick. The metal is then mechanically formed,
For example, it is sheared to a predetermined size and punched into a tray shape. The punched trays are then cleaned by tamping and degreasing, bead bombarded to texture the surface, and
Brush last. After the inspection, the tray thus manufactured is oxidized in advance to form an oxide film 21.

Conditions suitable for this preliminary oxidation are shown in Table (2).

Table ■ Range Favorable conditions temperature ('C) 1093~+204 115
0 endothermic gas is the product of incomplete combustion of a hydrocarbon fuel, such as methane, in air and contains about 4
0-53%, hydrogen 18-37?6, - carbon oxide approx. 12
~20% water vapor, 3% to 12% water vapor, less than about 3% carbon dioxide and small amounts of unreacted air and fuel. This endothermic gas is dried to a dew point of 10-30° C. for use in oxidizing metal to form the silicon oxide chip tray of the present invention.

Preferably, after oxidation, the oxidation tray is cooled to normal temperature (room temperature) and subjected to a smoothing operation. When the oxidation tray is flat, it is then heated at a temperature of about 77°C to about 732°C.
It is subjected to an aging-hardening treatment in air, which is carried out for hours. Advantageously, aging is carried out at about 704°C for about 3 hours. Those skilled in the art will recognize that other time and temperature combinations can be used to age-harden advantageous alloys such as those listed in Table H and other age-hardenable alloys within the broad alloy range described above. will.

Regarding thermal oxidation temperatures, temperatures below about 1080°C should generally be avoided since oxide films produced at temperatures below about 1080°C are thin and do not provide adequate radiative properties. At temperatures above about 1200°C, the oxides produced become less resistant to hydrofluoric acid;
The oxide film quickly becomes so thick that there is a risk of it peeling off from the tray surface.

Although the above examples are for thermal oxidation, it is also possible to oxidize chemically using reagents such as persalts, chromic acid, and/or oxidize chemically/thermally.

Reference has been made in detail to tray-simulating structures made from alloys within range A of Table 1 and processed as disclosed herein, which when cycled between room temperature and 593° C. It was found to be much more resistant to thermal warping than structures made from (lNC0NEI,)600 alloy. The oxide films formed on these structures are adhesive, have suitable radioactivity properties, and are resistant to hydrofluoric acid.

While certain aspects of the invention have been illustrated and described herein in accordance with the provisions of the statute, those skilled in the art will recognize that modifications may be made within the scope of the claims and that other features of the invention may be realized. It will be appreciated that the features of can sometimes be used advantageously without the corresponding use.

[Brief explanation of the drawing]

1 and 2 are a plan view and a sectional view of a portion of the tray, respectively, and FIG. 3 is an enlarged view of the tray surface having a highly radioactive oxide film. 11... Tray surface, 21... Oxide film, 23...
·metal.

Claims (1)

Claims: 1. By weight, nickel minimum about 70%, carbon up to about 0.2%, iron about 0.1 to about 20%, silicon about 0.05 to about 0.
8%, chromium about 10 to about 23%, aluminum about 0.2
- about 1.5%, titanium about 1.5 to about 3%, total of niobium and tantalum about 0.1 to about 3%, zirconium 0.2%
A silicon chip processing tray made from an age-hardened alloy containing up to about 0.03% boron and about 2 to about 4.5% aluminum, titanium, and silicon, the tray comprising: 1. A tray for processing silicon chips, characterized in that it has on its surface a thin adhesive highly radiant oxide film that is resistant to the action of aqueous hydrofluoric acid. 2. Made from an alloy having a range (% by weight) of Alloy A or Alloy B as specified below:
Tray for silicon chip processing as described in section. Element: Alloy A: Alloy B Carbon: Maximum 0.08: Maximum 0.08 Manganese: Maximum 1.0: Maximum 1.0 Iron: 5-9: 5-9 Sulfur: Maximum 0.01: Maximum 0.01 Silicon : Maximum 0.5: Maximum 0.5 Copper: Maximum 0.5: Maximum 0.5 Chromium: 14-17: 14-17 Aluminum: 0.4-1.0: 0.9-1.5 Titanium: 2 .25-2.75: 2.0-2.6 Niobium and tantalum: 0.7-1.2: 0.7-1.2 Nickel: Balance 70: Balance 70 3. Nickel minimum approximately 70% in weight% , up to about 0.2% carbon, about 0.1% to about 20% iron, and about 0.05% to about 0.0% silicon.
8%, chromium about 10 to about 23%, aluminum about 0.2
- about 1.5%, titanium about 1.5 to about 3%, total of niobium and tantalum about 0.1 to about 3%, zirconium 0.2%
mechanically forming an age-hardening alloy containing up to about 0.03% boron and about 2 to about 4.5% aluminum, titanium, and silicon into a tray structure; about 1093 to 120 in a moist endothermic gas
Thin adhesive high radiation resistant to the action of aqueous hydrofluoric acid characterized by heating for about 0.25 to 2 hours at a temperature in the range of 4° C. and then age hardening the alloy of said tray. A method for manufacturing a silicon chip processing tray having a functional oxide film.