CN102751208A - Monitoring method of rapid thermal processing equipment - Google Patents

Abstract

A monitoring method for rapid thermal annealing equipment, performing ion implantation on a product wafer, and performing rapid thermal annealing treatment on it, and then measuring the thermal wave data of the inner pad area of the die on the product wafer, and The thermal wave data is sent to the SPC equipment for processing, so that the state of the rapid thermal annealing equipment can be understood in a timely and accurate manner, and the rapid thermal annealing equipment can be adjusted at any time according to the needs, so that the rapid thermal annealing process results of each batch of wafers Stable and consistent.

Description

Monitoring method of rapid heat treatment equipment

technical field

The invention relates to a semiconductor manufacturing method, in particular to a method for monitoring rapid thermal annealing equipment in the semiconductor manufacturing process.

Background technique

Rapid thermal anneal (rapid thermal anneal, RTA) is a common process step in the semiconductor manufacturing process, and in order to obtain the best process effect, the state of the equipment is monitored (monitor), and then adjusted in time, which is essential for all rapid thermal annealing equipment (RTAtool), are essential. At present, the common method for monitoring rapid thermal annealing equipment in the industry is: first, place the bare wafer (bare wafer) in a standard and stable ion implantation equipment (IMP tool) for ion implantation, and then, The ion-implanted bare wafer is moved into a rapid thermal annealing device for rapid annealing treatment, and finally, resistivity (resistivity, Rs) or thermal wave (thermalwave, TW) data of the bare wafer is measured. If the rapid thermal annealing equipment is stable, then the measured resistivity or thermal wave value of the bare wafer will also be stable. Referring to accompanying drawing 1, have shown the flow chart of conventional method. The bare wafer 100 is first implanted with ions, and then undergoes rapid thermal annealing, measures the resistivity or thermal wave data, and sends the measured values to the statistical process control (Statistical Process Control, SPC) equipment, so as to realize the control of the rapid thermal annealing equipment. Monitoring and Control.

However, the above method also has some problems. First of all, the state of rapid thermal annealing equipment cannot be monitored in time, because the routine monitoring schedule is once every 24 hours or 48 hours. Thousands or even tens of thousands of wafers are processed, and the status of the rapid thermal annealing equipment is not monitored when these wafers are processed. In addition, the bare wafer used for monitoring is different from the product wafer (product wafer) used to manufacture integrated circuits, that is to say, the sensitivity of the monitoring wafer and the product wafer to the rapid thermal annealing equipment is not the same , thus, the bare wafer used for monitoring cannot accurately reflect the true state of the rapid thermal annealing equipment.

Therefore, it is necessary to develop a new monitoring method for rapid thermal annealing equipment, which can timely and accurately obtain status data about rapid thermal annealing equipment, so that the rapid thermal annealing process results of each batch of wafers are stable and consistent .

Contents of the invention

The invention provides a monitoring method for rapid thermal annealing equipment, which uses product wafers to monitor the rapid thermal annealing equipment, so that the status data of the rapid thermal annealing equipment can be obtained in a timely and accurate manner, and the stability of the rapid thermal annealing process can be ensured and consistency.

The invention provides a monitoring method for rapid thermal annealing equipment, comprising:

providing a plurality of product wafers for manufacturing the desired integrated circuits, each of the product wafers having a plurality of dies;

The die includes a pad area for electrically connecting the die to an external circuit;

placing a plurality of the product wafers in ion implantation equipment for ion implantation;

After performing the ion implantation, placing a plurality of the product wafers in a rapid thermal annealing device, and performing a rapid thermal annealing process on the plurality of product wafers;

After the rapid thermal annealing treatment, a data measurement step is performed;

Wherein, the data measurement step includes:

After performing rapid thermal annealing, take out any one or more of the multiple product wafers, measure the thermal wave data of the pad region in the die of the product wafer that has been taken out, and then take the The thermal wave data is sent to the statistical process control equipment, and the state of the rapid thermal annealing equipment is monitored through statistics and analysis of the thermal wave data.

In the method of the present invention, a plurality of the product wafers are subjected to rapid thermal annealing in different batches, and after each batch of rapid thermal annealing, the data measurement step is performed.

In the method of the present invention, a plurality of the product wafers are subjected to rapid thermal annealing in different batches, and after every 5 or 10 batches of rapid thermal annealing, the data measurement step is performed once.

In the method of the present invention, the data measuring step is carried out once every 2, 3 or 4 hours of continuous operation of the rapid thermal annealing device.

The advantage of the present invention is that: after the ion implantation process is performed on the product wafer, it is subjected to rapid thermal annealing treatment, and the thermal wave data is measured on the inner pad area of the die on the product wafer, and the thermal wave data is sent to SPC equipment for processing, so that the state of the rapid thermal annealing equipment can be understood in a timely and accurate manner, and then the rapid thermal annealing equipment can be adjusted at any time according to the needs, so that the rapid thermal annealing process results of each batch of wafers are stable and consistent.

Description of drawings

Fig. 1 monitors the conventional method process for rapid thermal annealing equipment;

Fig. 2 present invention monitors the flow chart of the method for rapid thermal annealing equipment;

Fig. 3 is the measurement details of the monitoring of the rapid thermal annealing equipment by the present invention.

Detailed ways

The features and technical effects of the technical solution of the present invention will be described in detail below with reference to the accompanying drawings and in combination with exemplary embodiments.

The present invention provides a monitoring method for rapid thermal annealing equipment. The process flow of the monitoring method is shown in Figure 2, and the measurement details are shown in Figure 3. The monitoring method specifically includes the following steps:

First, a plurality of product wafers 200 are provided. Product wafer (product wafer) 200 is used for manufacturing required integrated circuit (IC), prepares to carry out ion implantation; Meanwhile, each product wafer 200 all has a plurality of dies 201, and a plurality of dies 201 are criss-crossed The scribe slots are separated. There are also a plurality of pad regions 202 inside the die 201 , and the pad regions 202 are used to electrically connect the die 201 to external circuits.

Next, a plurality of product wafers 200 are placed in an ion implantation device (IMP tool) for ion implantation. The ion implantation equipment is standard and stable, so it also needs to be monitored and controlled in time to obtain stable ion implantation results, otherwise, it will affect the monitoring results of the rapid thermal annealing equipment.

Next, after ion implantation, the product wafer 200 is placed in a rapid thermal annealing (RTA) device for rapid thermal annealing. The duration of the rapid thermal annealing is determined by the parameters of the semiconductor device and the process parameters of the rapid thermal annealing equipment; the batch required for the rapid thermal annealing process is determined by the quantity of product wafers 200 and the batch processing capacity of the rapid thermal annealing.

After the rapid thermal annealing process, a data measurement step is performed. Referring to accompanying drawing 3, the data measurement step specifically comprises: take out any product wafer 200, measure the thermal wave data (TW) of pad region 202 in the tube core 201 of the product wafer 200 that takes out, then, described thermal wave The data is sent to statistical process control (SPC) equipment, and the status of the rapid thermal annealing equipment is monitored through statistics and analysis of the thermal wave data. In order to measure the data more accurately reflect the state of the rapid thermal annealing equipment, five areas can be selected on the taken out wafer for measurement.

In order to obtain data about the state of the rapid thermal annealing equipment in the most timely manner, one or more product wafers 200 may be taken out for data measurement after each batch of rapid thermal annealing process is completed, although this will waste process time. In order to achieve a balance between the timeliness of data collection and the time consumption of the entire process, the frequency of data measurement steps can be set according to the specific conditions of the rapid thermal annealing equipment and process, for example, 5 or 10 rapid annealing After thermally annealing the batch, a data measurement step is performed. Among them, regarding the selection of the measurement batch, the importance of the product and the capacity of the fab can be considered, and the selection can be made according to the mantissa of the wafer batch number. One batch; select 0, 5, that is to measure one batch every 5 batches; select all 0-9, that is, measure all products.

In the actual production process, the rapid thermal annealing equipment usually runs continuously 24 hours a day, and you can choose to perform a data measurement step after the ion implantation equipment runs continuously for 2, 3 or 4 hours. At the same time, when a fab with a small output or a recession in the semiconductor industry may not produce silicon wafers for a long time, it is also possible to consider measuring by time, such as measuring every batch, or performing a data measurement step every two days .

In the present invention, after the ion implantation process is performed on the product wafer, it is subjected to rapid thermal annealing treatment, and the thermal wave data is measured on the inner pad area of the die on the product wafer, and the thermal wave data is sent to the SPC equipment to process. Since the present invention detects product wafers rather than bare wafers, it is more direct than traditional methods to realize the ability to know the state of rapid thermal annealing equipment in a timely and accurate manner, and then can perform rapid thermal annealing equipment at any time as required. The control makes the rapid thermal annealing process results of each batch of wafers stable and consistent.

Although the present invention has been described with reference to the above exemplary embodiments, those skilled in the art can know that various suitable changes and equivalents can be made to the technical solutions of the present invention without departing from the scope of the present invention. In addition, many modifications, possibly suited to a particular situation or material, may be made from the disclosed teaching without departing from the scope of the invention. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode for carrying out this invention, but that the disclosed device structures and methods of making the same will include all embodiments falling within the scope of the invention .

Claims (4)

1. a monitoring method of rapid thermal annealing equipment, is characterized in that, described method comprises: providing a plurality of product wafers for manufacturing the desired integrated circuits, each of the product wafers having a plurality of dies; The die includes a pad area for electrically connecting the die to an external circuit; placing a plurality of the product wafers in ion implantation equipment for ion implantation; After performing the ion implantation, placing a plurality of the product wafers in a rapid thermal annealing device, and performing a rapid thermal annealing process on the plurality of product wafers; After the rapid thermal annealing treatment, a data measurement step is performed; Wherein, the data measurement step includes: After performing rapid thermal annealing, take out any one or more of the multiple product wafers, measure the thermal wave data of the pad region in the die of the product wafer that has been taken out, and then take the The thermal wave data is sent to the statistical process control equipment, and the state of the rapid thermal annealing equipment is monitored through statistics and analysis of the thermal wave data. 2. the monitoring method of rapid thermal annealing equipment as claimed in claim 1 is characterized in that, a plurality of described product wafers are divided into different batches to carry out rapid thermal annealing, and after each batch of rapid thermal annealing, all carry out all The data measurement steps described above. 3. The monitoring method of rapid thermal annealing equipment as claimed in claim 1, is characterized in that, multiple described product wafers are divided into different batches and carry out rapid thermal annealing, after every 5 or 10 batches of rapid thermal annealings , performing the data measuring step once. 4. The monitoring method of rapid thermal annealing equipment according to claim 1, characterized in that the data measuring step is performed once after the rapid thermal annealing equipment runs continuously for 2, 3 or 4 hours.

Images