JP2005347583A - Method of deciding heat treatment condition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce time until deciding a heat treatment condition that the electric characteristic of a semiconductor element after heat treatment reaches prescribed performance. <P>SOLUTION: This method comprises a heat treatment step of locally heat-treating one of a plurality of semiconductor elements formed on a wafer using a local heater in a measurement instrument, a step of measuring the electric characteristic of the semiconductor element heat-treated locally in the measurement instrument, a step of performing the heat treatment step and the measurement step by varying the condition of heat treatment about the other semiconductor elements of the plurality of semiconductor elements when the measured electric characteristic of the semiconductor element has not reached desired performance yet, and a step of deciding the condition of heat treatment performed to the semiconductor element as a desired heat treatment condition when the measured electric characteristic of the semiconductor element has reached desired performance. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a heat treatment condition determining method for determining a heat treatment condition such that electrical characteristics of a semiconductor element after the heat treatment reach a desired performance.

  In the manufacture of a field effect transistor, a gate insulating film and a gate electrode are formed on a semiconductor substrate, ions are implanted into the semiconductor substrate to form a source / drain region, and then about 1000 ° C. to activate the source / drain region. The heat treatment is performed.

  In this heat treatment, it is necessary to set heat treatment conditions according to the laminated structure of the field effect transistor, the film thickness or composition of each film. This is particularly important when an insulating film (High-K film) having a dielectric constant higher than that of the silicon oxide film is used as the gate insulating film.

  A conventional method for determining a heat treatment condition of a semiconductor element will be described with reference to FIG. 5 (see, for example, Patent Document 1). First, an evaluation semiconductor element is formed on a wafer (step S11). Next, the wafer is set on the measuring instrument (step S12). Then, the entire wafer is heat treated (step S13).

  Next, the electrical characteristics of the semiconductor element formed on the wafer are measured (step S14). It is determined whether or not the measured electrical characteristics of the semiconductor element have reached a desired performance (step S15). If the electrical characteristics of the semiconductor element do not reach the desired performance, steps S12 to S15 are performed on another wafer while changing the heat treatment conditions. On the other hand, if the electrical characteristics of the semiconductor element have reached the desired performance, the conditions for the heat treatment performed on the semiconductor element are determined as the target heat treatment conditions (step S16).

  When heat treatment of the semiconductor element is performed under the heat treatment conditions obtained by the above method, the electrical characteristics of the semiconductor element can be set to desired performance.

JP 2000-252331 A

  In the conventional method for determining the heat treatment conditions, since the entire wafer is heat treated, one wafer is used for one heat treatment condition. Therefore, it is necessary to prepare wafers for the number of times of measurement until the electrical characteristics of the semiconductor element reach a desired performance. In addition, there is a problem that a time for exchanging the wafer is required for each measurement, and the time required for determining the heat treatment condition becomes long.

  On the other hand, if the wafer is divided for each semiconductor element to be evaluated to form a wafer piece, the number of wafers can be suppressed. However, an apparatus for processing wafer pieces is required. In addition, it takes time to replace the wafer piece for each measurement, and the time required for determining the heat treatment conditions cannot be shortened.

  The present invention has been made in order to solve the above-described problems, and its purpose is to determine the heat treatment conditions so that the electrical characteristics of the semiconductor element after the heat treatment reach a desired performance. It is possible to obtain a heat treatment condition determination method capable of shortening the time of the heat treatment.

  A heat treatment condition determining method according to the present invention includes a heat treatment step in which one of a plurality of semiconductor elements formed on a wafer is locally heat treated using a local heater in the measuring instrument, and in the measuring instrument, A measurement step for measuring the electrical characteristics of the locally heat-treated semiconductor element, and if the measured electrical characteristics of the semiconductor element do not reach the desired performance, change the heat treatment conditions for other semiconductor elements in the plurality of semiconductor elements. A step of performing a heat treatment step and a measurement step, and a step of determining a heat treatment condition performed on the semiconductor element as a target heat treatment condition if the measured electrical characteristics of the semiconductor element have reached a desired performance; Have Other features of the present invention will become apparent below.

  According to the present invention, when determining the heat treatment conditions such that the electrical characteristics of the semiconductor element after the heat treatment reach a desired performance, the time until the determination can be shortened.

  A heat treatment condition determining method according to an embodiment of the present invention for determining a heat treatment condition that allows the electrical characteristics of the semiconductor element after the heat treatment to achieve a desired performance will be described with reference to FIG.

  First, a plurality of semiconductor elements for evaluation are formed on a wafer (step S1). Next, the wafer is set in the measuring instrument (step S2). In the measuring instrument, one or two of the plurality of semiconductor elements formed on the wafer are locally heat-treated using a local heater (step S3).

  Here, a case where a lamp annealing apparatus is used as the local heater will be described. FIG. 2 is a slope view of a local heater used for heat treatment.

  A local heater 12 is disposed on a wafer 11 on which a plurality of semiconductor elements are formed. The housing 13 of the local heater 12 is provided with a heat source 14 for heat treating the semiconductor element. The heat source 14 is controlled by a signal supplied from a control signal line 15.

  A gas supply unit 16 is provided around the heat source 14 to control the atmosphere around the semiconductor element during the heat treatment. A pipe 17 for supplying gas to the gas supply unit 16 for controlling the atmosphere is provided. Further, a gas discharge port 20 is provided on the side surface of the lower portion of the housing 13.

  In addition, the casing 13 is provided with a vertical movement unit 18 for moving the local heater 12 up and down with respect to the wafer 11. The vertical movement unit 18 is controlled by a signal supplied from a control signal line 19.

  FIG. 3 is a bottom view of the local heater. Legs 21 that come into contact with the wafer 11 are provided at the four corners of the bottom surface of the housing 13. Further, the tip of the heat source 14 is exposed at the center of the bottom surface of the housing 13. And the gas supply port 22 of the gas supply part 16 is opening in the circumference | surroundings.

  FIG. 4 is a view showing the tip of the heat source of the local heater. A filament 24 is installed in the outer shield 23 in a reduced pressure inert gas atmosphere. A light collector 25 for collecting the light generated by the filament 24 on the wafer 11 is provided behind the filament 24. Thereby, the range to be heat-treated using a local heater can be a spot having a diameter of about 100 μm, and one or two semiconductor elements formed on the wafer can be locally heat-treated.

  In addition, the filament 24 is drawn backward via a filament insulator 26 that prevents contact with the light collector 25 and is connected to the control signal line 15 although omitted in the middle.

  Next, the operation of the local heater in the heat treatment step will be described. First, the local heater 12 is disposed on the wafer 11, moved in the horizontal direction by a mechanism not shown, and aligned with a semiconductor element to be heat-treated.

  Next, the local heater 12 is moved by the up-and-down moving unit 18 until it comes into contact with the wafer 11 and is pressed against the wafer 11 with a certain force even after the contact. Thereafter, nitrogen gas mixed with inert gas, nitrogen gas, or a small amount of oxygen gas is supplied from the gas supply port 22 of the gas supply unit 16 around the semiconductor element to be heat-treated. The supplied gas is discharged from the gas discharge port 20.

  Next, electricity is supplied to the filament 24 provided at the tip of the heat source 14 to generate light, and this light is collected by the light collecting plate 25 and only on the region including the semiconductor element to be heat-treated on the wafer 11. Irradiated. Thereby, about one or two of the plurality of semiconductor elements formed on the wafer 11 are locally heated.

  After the heat treatment is completed, the local heater 12 is moved upward by the up-and-down moving unit 18, moved in the horizontal direction, and removed from the wafer 11.

  Next, the electrical characteristics of the locally heat-treated semiconductor element are measured in the same measuring device (step S4). Then, it is determined whether or not the measured electrical characteristics of the semiconductor element have reached a desired performance (step S5). Here, if the measured electrical characteristics of the semiconductor elements do not reach the desired performance, steps S3 to S5 are performed for other semiconductor elements that are not subjected to heat treatment of a plurality of semiconductor elements on the same wafer by changing the heat treatment conditions. I do. On the other hand, when the measured electrical characteristics of the semiconductor element reach the desired performance, the conditions for the heat treatment performed on the semiconductor element are determined as the target heat treatment conditions (step S6).

  In this way, one of the plurality of semiconductor elements formed on the wafer is locally heat-treated, and the electric characteristics of the semiconductor element after the heat treatment are evaluated, whereby the electric characteristics of the semiconductor elements on one wafer are evaluated. The evaluation can be repeated by changing the heat treatment conditions. Therefore, since it is not necessary to replace the wafer for each measurement, the time for wafer replacement can be saved, and the time required for obtaining the heat treatment conditions that achieve the desired performance of the semiconductor element after heat treatment can be shortened. can do.

It is a flowchart which shows the heat treatment condition determination method which concerns on embodiment of this invention. It is a slope view which shows a local heater. It is a bottom view which shows a local heater. It is a figure which shows the front-end | tip part of the heat source of a local heater. It is a flowchart which shows the conventional heat processing condition determination method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Wafer 12 Local heater 13 Case 14 Heat source 15 Control signal line 16 Gas supply part 17 Pipe 18 Vertical movement part 19 Control signal line 20 Gas discharge port 21 Leg part 22 Gas supply port 23 External shield 24 Filament 25 Light collector 26 Filament Insulation

Claims (4)

A heat treatment step of locally heat-treating one of a plurality of semiconductor elements formed on the wafer using a local heater in the measuring instrument;
In the measuring device, a measuring step for measuring electrical characteristics of the locally heat-treated semiconductor element;
If the measured electrical characteristics of the semiconductor elements do not reach the desired performance, the heat treatment step and the measurement step by changing the heat treatment conditions for the other semiconductor elements of the plurality of semiconductor elements,
A method for determining a heat treatment condition, comprising: determining a heat treatment condition performed on the semiconductor element as a target heat treatment condition when the measured electrical characteristics of the semiconductor element reach a desired performance .   2. The heat treatment condition determining method according to claim 1, wherein a lamp annealing apparatus is used as the local heater.   The heat treatment condition determination method according to claim 1 or 2, wherein a range to be heat-treated using the local heater is a spot having a diameter of about 100 µm.   4. In the heat treatment step, an atmosphere around the semiconductor element to be heat-treated is an inert gas, a nitrogen gas, or a nitrogen gas mixed with a trace amount of oxygen gas. The heat treatment condition determination method according to 1.

Images