TW201331568A - Photoluminescence measuring system and measuring method thereof - Google Patents

Abstract

A photoluminescence measuring system includes a first light path sequentially constituted of an exciting light source, a splitter, a reflector, and a table. The reflector has a through hole corresponding to the first light path. When the exciting light source emits an emitting light beam along the first light path, the emitting light beam penetrates the splitter and illuminates directly an object to be measured on the table to form a photoluminescence, and make the photoluminescence illuminates a measuring device via the reflector to process a photoluminescence measurement, to prevent from the decay of the photoluminescence. It is also disclosed a measuring method using the said photoluminescence measuring system.

Description

Fluorescence reaction detection system and detection method thereof

The present invention relates to a fluorescent reaction detecting system and a method of using the same, and more particularly to a photoluminescence measuring system and a method of using the same.

In the fabrication of a light-emitting diode wafer, a semiconductor material capable of emitting light after being energized is generally used to form a plurality of light-emitting diode wafers on a whole wafer, and then a plurality of light-emitting diode wafers are singulated. to make. After the semiconductor material is energized, the electrons will jump from the ground state to the excited state, and then fall from the excited state to the lower energy band, and at the same time emit electromagnetic waves. When the wavelength of the electromagnetic wave falls within the visible range, such a semiconductor is usually used as a material of the light-emitting device. In addition, when the semiconductor material of the LED chip is irradiated with light of a specific wavelength, the electron also jumps from the ground state to the excited state, and generates an electron hole pair, and the electron hole pair will recombine and emit fluorescence. This phenomenon of fluorescence reaction is commonly referred to as "photoluminescence" (PL).

In general, if the LED chip is defective, the spectrum of the fluorescence changes. Therefore, the general manufacturer will manually illuminate each of the light-emitting diode chips with light of a specific wavelength after singulation, thereby causing the semiconductor material of the light-emitting diode to emit fluorescence to detect the light-emitting diode. Whether the wafer process is perfect or not. By analyzing the spectral information of the fluorescent light, the material characteristics and defects of the light-emitting diode wafer can be known. This detection method is called a fluorescence reaction detection method or a photoluminescence detection method. Relative to the semiconductor material of the LED chip, the fluorescence reaction detection method is a non-destructive detection technique because the selected light energy is not strong. However, if the fluorescence is to be successfully excited, the energy of the excitation source must be greater than the energy gap of the semiconductor material. Since most semiconductor materials have an energy gap of less than 3 eV, the wavelength of the excitation source is usually not greater than the green range if converted.

In addition, in the conventional fluorescence reaction detection system, the alignment of the experimental samples can only be directly discriminated and aligned by the human eye. However, in addition to manual detection and time-consuming labor, most of the fluorescence is not strong, so whether the detection system can automatically detect and avoid the decrease of the fluorescence intensity when detecting the fluorescence has become an important issue.

In view of the above problems, the present invention provides a fluorescence reaction detecting system and a detecting method thereof, which are capable of smoothly passing through a mirror by using a mirror having a through hole, and fluorescing the fluorescent reaction light. Largely collected into the detection device to reduce the escape of photoluminescence.

The invention provides a fluorescence reaction detection system, which mainly comprises an excitation light source, a beam splitter, a mirror, a worktable, a positioning device and a detecting device. The excitation light source, the beam splitter, the mirror, and the table sequentially form a first optical path. The worktable, the mirror, the beam splitter and the positioning device form a second optical path in sequence. The table, the mirror and the detecting device sequentially form a third optical path. The excitation light source emits an outgoing light along the first optical path, and the emitted light passes through the beam splitter and the mirror to be irradiated to the workbench. After the emitted light is irradiated on one of the objects to be detected on the workbench, a reflected light and a photo-induced fluorescent light are formed, and the reflected light is irradiated to the positioning device along the second optical path. The photoluminescence is irradiated to the detecting device along the third optical path. The mirror has a through hole corresponding to the first light path, so that the emitted light is directly irradiated to the object to be detected after passing through the beam splitter.

The present invention provides a detection method using the above-described fluorescence reaction detecting system, which comprises the following steps. The emitted light is irradiated along the first optical path to the position to be detected of the object to be detected. The positioning device can compare the position irradiated by the outgoing light with the position to be tested along the second optical path. When the position to be tested coincides with the position illuminated by the emitted light, the detecting device can detect the photoluminescence formed by the fluorescent reaction of the position to be tested along the third optical path. When the position irradiated by the emitted light does not match the position to be tested, the table is driven to be displaced so that the position to be detected of the object to be detected is moved to the position where the emitted light is irradiated. Next, another fluorescent reaction at the position to be tested is detected.

According to the fluorescent reaction detecting system and the detecting method thereof of the present invention, the object to be detected is automatically positioned by the arrangement of the second optical path, and by the configuration of the mirror having the through hole and the third optical path, The majority of the photoluminescence in the fluorescent reaction can be reflected by the mirror to the detecting device, so that the detecting device can receive a sufficient amount of photoluminescence to facilitate the accuracy of the detection result.

Please refer to FIG. 1 , which is a block diagram of a fluorescence reaction detecting system 10 according to an embodiment of the present invention. The fluorescence reaction detecting system 10 mainly includes a control unit 100, an excitation light source 110, a beam splitter 120, a mirror 130, a table 140, a detecting device 150, and a positioning device 160. The excitation light source 110, the beam splitter 120, the mirror 130, and the table 140 sequentially constitute the first optical path L1. The stage 140, the mirror 130, the beam splitter 120, and the positioning device 160 sequentially constitute the second optical path L2. The stage 140, the mirror 130, and the detecting device 150 sequentially constitute the third optical path L3. The center of the mirror 130 has a through hole 131, and the position of the through hole 131 corresponds to the first optical path L1. The table 140 is used to carry and move the position of the object to be inspected 200.

In this embodiment, the control unit 100 is, for example, a computer and a control program. The excitation light source 110 is, for example, a He-Cd laser, an Ar-ion laser, and a green laser. The beam splitter 120 is, for example, a beam splitter in which the transmittance and the reflectance are each half, and has a first reflecting surface 121, and the mirror 130 has a second reflecting surface 132. The second reflective surface 132 can be formed from an aluminized reflective layer. The table 140 can be, for example, a ball screw driven biaxial motion platform or a linear motor driven biaxial motion platform. Detection device 150 can be, for example, a spectrometer to produce a spectral distribution of the detected photoluminescence. The positioning device 160 is, for example, a charge-coupled device (CCD) image capturing device or a complementary metal-oxide-semiconductor (CMOS) image capturing device. The object to be detected 200 may be, for example, a wafer of light emitting diodes, and the semiconductor material contained therein may be, for example, aluminum gallium arsenide (AlGaAs), indium gallium phosphide (AlGaInP), gallium phosphide (GaP), nitriding. Materials such as gallium (GaN), indium gallium nitride (InGaN), gallium arsenide (GaAs), indium phosphide (InP), tantalum carbide (SiC), germanium (Si), and zinc selenide (ZnSe).

As shown in FIG. 1, the first optical path L1 passes through the excitation light source 110, the beam splitter 120, and the through hole 131 of the mirror 130, and reaches the table 140. The second optical path L2 passes through the table 140, through the through hole 131 of the mirror 130, and the first reflecting surface 121 of the beam splitter 120, and reaches the positioning device 160. The third optical path L3 passes through the table 140 and the second reflecting surface 132 of the mirror 130 to reach the detecting device 150. The excitation light source 110 can emit an outgoing light along the first optical path L1, and the emitted light can pass through the beam splitter 120 and be irradiated to the table 140 through the through hole 131 of the mirror 130, so that the emitted light is transmitted through the beam splitter 120. Thereafter, it is possible to directly illuminate the object to be detected 200. The emitted light can form a reflected light after being irradiated to the object to be detected 200. The reflected light is irradiated to the positioning device 160 along the second optical path L2. In addition, the emitted light can form a photoluminescence in addition to forming a reflected light, which can be irradiated to the detecting device 150 along the third optical path L3. .

In the present embodiment, the fluorescence reaction detecting system 10 can also include a strip pass filter 111 between the excitation light source 110 and the beam splitter 120. The band pass filter 111 has a very low light transmittance for light of a non-specified wavelength range, and thus can filter out light of an undesired wavelength in the emitted light. In addition, between the beam splitter 120 and the positioning device 160, the fluorescence reaction detecting system 10 can further include a long wave pass filter 161, and between the mirror 130 and the detecting device 150, the fluorescent reaction detecting system 10 also A further long pass filter 152 can be included. The cut wavelengths of the long pass filters 161 and 152 are larger than the wavelengths required for the outgoing light, and the long pass filters 161 and 152 have extremely low transmittance for light having a shorter cutoff wavelength. Therefore, the long-wavelength filters 161 and 152 can respectively protect the positioning device 160 and the detecting device 150 from the damage of the emitted light emitted by the excitation light source 110 and the reflected light thereof.

In addition, in the present embodiment, between the mirror 130 and the detecting device 150, the fluorescent reaction detecting system 10 can further include a concentrating mirror 153, and the detecting device 150 can further include an optical fiber 151. The condensing mirror 153 can collect the photoluminescence and illuminate the optical fiber 151, and then guide the photoluminescence to the detecting device 150 by the optical fiber 151. Between the mirror 130 and the table 140, the fluorescence reaction detection system 10 can also include an auxiliary illumination source 170. The auxiliary illumination source 170 can be, for example, an annular source. The auxiliary illumination source 170 and the stage 140 sequentially form the fourth optical path L4. The auxiliary illumination light source 170 can be irradiated to the object to be detected 200 on the table 140 along the fourth optical path L4 to pass through the through hole 131 of the mirror 130 and the first reflective surface 121 of the beam splitter 120 (ie, via the second optical path L2) And the image of the object to be detected 200 is irradiated to the positioning device 160, so that the positioning device 160 can sense the image of the object to be detected 200 to facilitate the positioning of the object to be detected 200. The auxiliary illumination source 170 can emit light having a wavelength greater than the cutoff wavelength of the long pass filter 161. Furthermore, between the mirror 130 and the table 140, the fluorescence reaction detecting system 10 can further include a focusing mirror 180 for facilitating the excitation of the emitted light from the light source 110, which can be better focused on the table 140. The object to be tested 200 is on.

As shown in Fig. 1, this embodiment discloses a fluorescence reaction detecting method comprising the steps described below. The control unit 100 turns on the auxiliary illumination source 170 and adjusts the position of the table 140 on which the object to be detected 200 is placed. The light of the auxiliary illumination source 170 is directly irradiated to the object to be detected 200 along the fourth optical path L4. After the illumination light from the auxiliary illumination source 170 is irradiated to the object to be detected 200, it can pass through the second optical path L2, pass through the focusing mirror 180, pass through the through hole 131 of the mirror 130, and then pass through the first reflecting surface 121 of the beam splitter 120. After being reflected, it is protected by the long pass filter 161 and then sensed by the positioning device 160. Please refer to FIG. 2 at the same time, which shows a top view of the object to be tested 200 according to an embodiment of the present invention. The control unit 100 controls the table 140 and the positioning device 160 to scan the entire object to be detected 200 along the path W. The object to be detected 200 has a plurality of light emitting diode wafers 210. Please also refer to FIG. 3, which is a partial enlarged view of FIG. The positioning device 160 can sense and record the intersection position P1 between the plurality of LED wafers 210, that is, the corners of the LED wafer 210. The control unit 100 calculates and records the position to be tested P2 (ie, the intersection of the four corners of any one of the LED chips 210) according to the transfer positions P1.

Next, as shown in Fig. 1, the excitation light source 110 is turned on to emit an outgoing light along the first optical path L1. The exiting light passes through the bandpass filter 111 and filters out undesired wavelengths of light, passing only the exiting light having the desired wavelength. The emitted light penetrates the through hole 131 of the beam splitter 120 and the mirror 130, and is irradiated to the object to be detected 200 to form a reflected light. The reflected light will pass through the focusing mirror 180, the through hole 131 of the mirror 130 and the first reflecting surface 121 of the beam splitter 120 along the second optical path L2, and then irradiated to the positioning device 160 through the protection of the long pass filter 161 to The positioning device 160 is prevented from being damaged by direct irradiation of reflected light. The control unit 100 determines whether the emitted light is irradiated to the to-be-measured position P2 of one of the LED chips 210 of the object to be detected 200 by the position of the reflected light reflected in the positioning device 160, that is, the emitted light is compared. Whether the position irradiated corresponds to the position to be tested P2. When the emitted light is not irradiated to the position P2 to be measured of the LED chip 210, that is, the position where the emitted light is irradiated does not coincide with the position P2 to be measured, the table 140 is moved until the emitted light is irradiated to the position P2 to be tested. .

When it is determined that the emitted light is irradiated to the position P2 to be tested, the emitted light is irradiated to the object to be detected and a photoluminescence is formed due to the fluorescence reaction. The photoluminescence is transmitted through the focusing mirror 180, through the reflection of the second reflecting surface 132 of the mirror 130, and the condensing of the collecting mirror 153 and the long-wavelength filter 152, and then irradiated to the optical fiber 151 of the detecting device 150. . The detecting device 150 generates a spectrum according to the photoluminescence, and sends the spectrum to the control unit 100 for analysis to determine whether the LED chip 210 at the position P2 to be tested has a defect in the process.

After the emitted light is irradiated to the position P2 to be measured and the photoluminescence is formed, the table 140 moves according to the recorded plurality of positions P2 to be measured, so that the emitted light is irradiated to the other position P2 to be measured. Another photoluminescence is formed. When all of the light-emitting diode chips 210 of the entire object to be detected 200 are completely detected, the detection of the detected object 200 is completed.

In summary, the fluorescence reaction detecting system and method of the present invention enables the positioning device to sense the image of the object to be detected by the arrangement of the second optical path, and can sense the reflected light to determine whether the emitted light is irradiated. The position of the object to be tested is to be tested to facilitate the positioning of the light and the object to be detected, thereby improving the accuracy of the detection result. Furthermore, since the mirror having the hole is disposed in the second optical path, the image of the object to be detected and the reflected light can be smoothly passed through the mirror. In addition, by the arrangement of the third optical path, the photo-induced fluorescence generated by the fluorescent reaction can be mostly reflected by the mirror to the detecting device, so that the detecting device can receive a sufficient amount of photo-induced fluorescence to facilitate The accuracy of the test results. In this way, in the fluorescence reaction detecting system of the present invention, since the image capturing and detecting device fluorescent detection of the positioning device is integrated, the user can directly perform the fluorescence reaction after observing the object to be detected. Photoluminescence measurement. In addition to its more accurate positioning, it can further reduce the time spent between observation and inspection, and at the same time confirm the position of the laser on the object to be detected.

Although the present invention has been disclosed above in the foregoing embodiments, it is not intended to limit the invention. It is within the scope of the invention to be modified and modified without departing from the spirit and scope of the invention. Please refer to the attached patent application for the scope of protection defined by the present invention.

10. . . Fluorescence reaction detection system

100. . . control unit

110. . . Excitation source

111. . . Bandpass filter

120. . . Beam splitter

121. . . First reflecting surface

130. . . Reflector

131. . . Hole through

132. . . Second reflecting surface

140. . . Workbench

150. . . Testing device

151. . . optical fiber

152, 161. . . Long pass filter

153. . . Condenser

160. . . Positioning means

170. . . Auxiliary illumination source

180. . . Focusing mirror

200. . . Object to be detected

210. . . Light-emitting diode chip

L1. . . First light path

L2. . . Second light path

L3. . . Third light path

L4. . . Fourth light path

P1. . . Handover location

P2. . . Position to be tested

W. . . path

Figure 1 is a block diagram showing a fluorescent reaction detecting system in accordance with an embodiment of the present invention.

2 is a top plan view of an object to be inspected 200 in accordance with an embodiment of the present invention.

Fig. 3 is a partial enlarged view of Fig. 2.

10. . . Fluorescence reaction detection system

100. . . control unit

110. . . Excitation source

111. . . Bandpass filter

120. . . Beam splitter

121. . . First reflecting surface

130. . . Reflector

131. . . Hole through

132. . . Second reflecting surface

140. . . Workbench

150. . . Testing device

151. . . optical fiber

152, 161. . . Long pass filter

153. . . Condenser

160. . . Positioning means

170. . . Auxiliary illumination source

180. . . Focusing mirror

200. . . Object to be detected

L1. . . First light path

L2. . . Second light path

L3. . . Third light path

L4. . . Fourth light path

Claims (10)

A fluorescence reaction detecting system includes an excitation light source, a beam splitter, a mirror, a working table, a positioning device and a detecting device; the excitation light source, the beam splitter, the mirror and the table are Forming a first optical path; the working table, the mirror, the beam splitter and the positioning device sequentially form a second optical path; the working table, the mirror and the detecting device sequentially form a third optical path The excitation light source emits an outgoing light along the first optical path, and the emitted light passes through the beam splitter and the mirror to be irradiated to the worktable; the emitted light is irradiated on the worktable to be detected After the object, a reflected light is formed, and the reflected light will be irradiated to the positioning device along the second optical path; and the emitted light will additionally form a photoluminescence after being irradiated to the object to be detected. The light is irradiated to the detecting device along the third optical path; wherein the mirror has a through hole corresponding to the first optical path and the second optical path, so that the emitted light is penetrated Directly after the beam splitter The object to be detected. The fluorescence reaction detecting system of claim 1, wherein after the emitted light is irradiated on the working table and forms a reflected light, the reflected light passes through the beam splitter through the second optical path, and passes through the beam. The beam splitter is irradiated to the positioning device. The fluorescence reaction detecting system of claim 1, wherein a band pass filter is further included between the excitation light source and the beam splitter. The fluorescence reaction detecting system of claim 1, wherein a long pass filter is further included between the beam splitter and the positioning device or the mirror and the detecting device. The fluorescence reaction detecting system of claim 1, wherein a condensing mirror is further included between the mirror and the detecting device. The fluorescence reaction detecting system of claim 1, wherein an auxiliary illumination source is further included between the mirror and the table. A fluorescence reaction detecting system according to claim 1, wherein a focusing mirror is further included between the mirror and the table. A method for detecting a fluorescence reaction detecting system according to claim 1, comprising the steps of: irradiating the emitted light along the first optical path to a position to be detected of the object to be detected; the positioning device can be along Whether the position of the second light path is more than the position of the emitted light and the position to be tested; and when the position to be tested matches the position illuminated by the emitted light, the detecting device may follow the first Three light paths are used to detect the fluorescence reaction of the position to be tested. The detecting method according to claim 8, wherein when the position irradiated by the outgoing light does not match the position to be tested, the table is driven to be displaced, so that the position to be tested of the object to be detected is moved to the The position at which the outgoing light is illuminated. The detecting method of claim 8, further comprising adjusting a position of the working table, so that the positioning device senses and records a plurality of to-be-measured positions of the object to be detected, and the third detecting device is along the third After detecting the fluorescence reaction of the position to be tested, the optical path is moved according to the recorded positions to be tested, so that the detecting device can detect another fire of the position to be tested along the third optical path. Photoreaction.