JPS60116128A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To prevent a thin oxide film from damaging and an inversion from occurring in a field by coating a conductive film on the entire surface of a semiconductor substrate before filling when implanting an impurity by an ion implating machine, thereby discharging the charge of electrostatic charge generated at the implanting time. CONSTITUTION:A thick field oxide film 4 is formed on the periphery of a semiconductor substrate 1, a thin oxide film 3 is coated on the surface of the substrate 1 surrounded by the film 4, and a conductive film 5 made of aluminum- doped polycrystalline Si is bonded to the entire surface including the film 3. Then, a mask 2 having the prescribed hole is formed to form an impurity layer in the prescribed region, impurity ions are implanted, and a desired impurity layer is formed in the substrate 1 through the film 5 and further the film 3 exposed in the hole. Thus, when the film 5 is formed at the impurity layer forming time, the electrostatic charge generated at the ion implanting time can be discharged from the film 5, thereby preventing the film 3 from damaging and an inversion from occurring under the film 4.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides 161 improvements to a method of manufacturing a semiconductor device using a step of implanting impurities into a semiconductor substrate by ion implantation.

FIG. 1 shows a conventional method of manufacturing a half-gage, integrated device.

When forming an impurity layer in the semiconductor substrate 1 by ion implantation, a thin oxide film 3 is passed through the mask 2 (for example, photoresist, 54o2', etc.) except for the ion implantation area (if there is no oxide film 3). ), perform ion implantation. In this method, the mask 2I oxide film 3.
Electric charges are generated near the surface of the field oxide film 40 and inside the field oxide film 40. Therefore, the oxide film 3 becomes a cause of elutriation due to the potential difference with the semiconductor substrate 1, and the inversion of the field portion due to the charging of the field oxide film 4. Conventional manufacturing methods have such drawbacks.

The object of the present invention is to provide a method for manufacturing a semiconductor device in which the above drawbacks are eliminated by forming a conductive film on the entire surface of a semiconductor substrate 1 before ion implantation, and then performing ion implantation.

An embodiment of the present invention will be described below with reference to FIG.

FIG. 2(b) shows that a conductive film 5 is applied to the entire surface of the semiconductor substrate 1 before the step of creating an impurity layer by ion implantation.
(e.g. Ai, doped Po1y 8i, etc.). Next, a normal ion implantation process is performed.

When creating an impurity layer at a certain location, as shown in FIG. 2 (6), a mask is deposited on the conductive film 5, followed by a photolithography process, patterning, and ion implantation. I do.

After completing the ion implantation process, mask 2. The conductive film 5 may be removed.

In the above embodiment, the process of performing ion implantation after the conductive film 5 has been completely deposited has been described. Next, the reverse process is shown in Figure 2 (
As shown in c), first put on what will become the mask 2,
Perform shiba patterning using photolithography. After that, a conductive coating is applied to the entire surface5. After deposition, it is possible to create an impurity layer by ion implantation. Further, although the above embodiment shows that an impurity layer is formed in a portion, even when implanting ions into the entire surface of the semiconductor substrate 1, the ion implantation can be performed after the conductive film 5 is deposited. It goes without saying that the object of the present invention can also be achieved.

As described above, when performing the ion implantation process after depositing the conductive film 5, the present invention prevents oxidation by discharging the electrostatic charge that occurs during ion implantation from the conductive film 5 and preventing charging. This has the effect of preventing membrane destruction and reversal in the field area. In order to prevent static electricity, a device called an electronic shower is attached to the ion implanter for ion implantation, but the presence of the gold layer of the present invention also has the effect of allowing ion implantation to be performed without using a device like a metal ion implanter. .

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing a conventional manufacturing method for forming an impurity layer by ion implantation, and FIGS. FIG. 1. Semiconductor substrate 2. Mask 8. Thin oxide film 4. Field oxide film 5. Conductive film or more

Claims (1)

[Claims] 1. A method for manufacturing a semiconductor device, which comprises depositing a conductive film over the entire surface of a semiconductor substrate 1 before ion implantation in a step of implanting impurities into a semiconductor substrate using an ion implanter.