High-transmittance glass chuck for chip defect positioning in EFA field

Abstract

The invention discloses a high-transmittance glass chuck for chip defect positioning in the EFA field, which comprises a glass main board, high-transmittance glass is arranged in an inner cavity of the glass main board, a glass pressing ring is arranged on the surface of the high-transmittance glass, a sliding groove and symmetrical mounting grooves are respectively formed in the bottom of the glass main board, and an adjusting block is slidably sleeved with an inner cavity of the sliding groove through a spring; an ejector block is installed in an inner cavity of the installation groove in a threaded mode, a wafer is installed between the adjusting block and the ejector block, an annular groove is formed in the surface of the glass main plate, and an air exhaust hole is formed in one end of the glass main plate. According to the high-transmittance glass chuck for chip defect positioning, through mechanical pre-clamping of the elastic adjusting blocks and vacuum adsorption of the air holes, the fastening force of a wafer is improved, the light transmittance, flatness and interference resistance of high-transmittance glass are improved, misjudgment caused by detection is avoided, the judgment rate is improved, the high-transmittance glass can be abutted and installed through the glass pressing ring, and the detection efficiency is improved. Operation is fast and simple.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of wafer detection, in particular to a high-transparency glass chuck for chip defect positioning in the EFA field. BACKGROUND

[0002] EFA (Electrical Failure Analysis) is a core link of post-packaging failure analysis of integrated circuits, aiming to provide accurate basis for subsequent physical failure analysis (PFA) through electrical characteristic detection, fault area positioning and failure mechanism analysis, and finally realize process optimization and reliability improvement.

[0003] The existing wafer glass chuck is a precision clamp specially used for wafer detection, and the existing wafer chuck adopts adhesive tape to bond the wafer, which is easy to fall off due to mechanical vibration or temperature change in the detection process.

[0004] There are two problems in the chip defect detection (such as InGaAs EMMI, Obirch & TIVA) of the ordinary glass stage: Insufficient light transmittance: the light transmittance of ordinary glass in the near-infrared waveband (1.3-1.55 μm) is only 80-85%, causing laser signal attenuation and affecting the sensitivity of the detector.

[0005] Thermal interference: the thermal conductivity of glass causes local temperature gradient during laser scanning, which causes thermal expansion difference to cause focusing deviation and false hot spot signal. SUMMARY

[0006] In view of the defects of the prior art, the application provides a high-transparency glass chuck for chip defect positioning in the EFA field, which solves the above problems.

[0007] To achieve the above purpose, the application realizes the following technical scheme: a high-transparency glass chuck for chip defect positioning in the EFA field, comprising a glass main plate, the inner cavity of the glass main plate is integrally extended to a limiting ring, and the surface of the limiting ring is provided with high-transparency glass, and the surface of the high-transparency glass is provided with a glass compression ring. The bottom of the glass main plate is respectively provided with a sliding groove and symmetrical mounting grooves, the inner cavity of the sliding groove is slidably sleeved with an adjusting block, a spring is arranged between the adjusting block and the sliding groove, the inner cavity of the mounting groove is screw-mounted with a top block, and a wafer is arranged between the adjusting block and the top block. The surface of the glass main plate is provided with a ring groove, one end of the glass main plate is provided with an air extraction hole, and the inner cavities of the air extraction hole and the ring groove are in communication.

[0008] Preferably, the edge of the high-transparency glass is matched with the inner cavity of the glass main plate.

[0009] Preferably, the glass pressing ring is abutted on the high-transparency glass.

[0010] Preferably, the glass pressing ring is fastened with the inner cavity of the glass main plate, and the surface of the glass pressing ring is flush with the surface of the glass main plate.

[0011] Preferably, the surface of the adjusting block and the middle protruding surface of the top block protrude from the surface of the glass main plate.

[0012] The application provides a high-transparency glass chuck for chip defect positioning in the field of EFA. 1. The high-transparency glass chuck for chip defect positioning improves the fastening force of the wafer through the mechanical pre-clamping of the elastic adjusting block and the vacuum adsorption of the air hole. 2. The high-transparency glass chuck for chip defect positioning facilitates the support of the die or small wafer through the high-transparency glass, and the light transmittance, flatness and anti-interference of the high-transparency glass can avoid misjudgment in the detection of the die or small wafer and improve the judgment rate.

[0013] 3. The high-transparency glass chuck for chip defect positioning can resist and install the high-transparency glass through the glass pressing ring, which is fast and simple to operate. DETAILED DESCRIPTION

[0014] Figure 1 is a structure top view of the application; Figure 2 is a structure bottom view of the application; Figure 3 is a structure exploded view of the application; Figure 4 is a structure of the application Figure 3 is a local enlarged view of A in the structure of the application; Figure 5 is a structure of the application Figure 3 is a local enlarged view of B in the structure of the application; Figure 6 is a structure limit ring schematic view of the application; Figure 7 is a local schematic view of the glass main plate of the structure of the application.

[0015] In the figure: 1, glass main plate; 11, air hole; 12, limit ring; 13, ring groove; 14, sliding groove; 15, spring; 16, installation groove; 2, wafer; 3, glass pressing ring; 4, high-transparency glass; 5, adjusting block; 6, top block. DETAILED DESCRIPTION

[0016] The technical solutions in the embodiments of the present application are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of the present application.

[0017] Please refer to Figures 1-7 The embodiment of the present application provides a technical solution: a high-transparency glass chuck for chip defect positioning in the field of EFA, comprising a glass main plate 1, a limiting ring 12 integrally extended in the inner cavity of the glass main plate 1, and a high-transparency glass 4 arranged on the surface of the limiting ring 12, a glass pressing ring 3 arranged on the surface of the high-transparency glass 4, the edge of the high-transparency glass 4 and the inner cavity of the glass main plate 1 are mutually attached, the glass pressing ring 3 is abutted on the high-transparency glass 4, the glass pressing ring 3 and the inner cavity of the glass main plate 1 are mutually fastened, and the surface of the glass pressing ring 3 and the surface of the glass main plate 1 are mutually flush. First, the high-transparency glass 4 is placed into the inner cavity of the glass main plate 1 and abutted on the limiting ring 12, and then the glass pressing ring 3 is fastened in the inner cavity of the glass main plate 1 and abutted on the high-transparency glass 4. The glass pressing ring 3 has elasticity, so that the glass pressing ring 3 can be squeezed into the inner cavity of the glass main plate 1, and the glass pressing ring 3 is loosened and fastened in the inner cavity of the glass main plate 1 under the elastic force, and the high-transparency glass 4 is also fixed. The installation is simple, and the high-transparency glass 4 achieves the following effects: Transmittance: Ensure that the infrared laser / signal penetrates without attenuation to avoid misjudgment.

[0018] Flatness: Nanometer-level surface precision to avoid focusing deviation.

[0019] Anti-interference: Low thermal conductivity reduces the influence of temperature gradient on Obirch & TIVA, both of which are laser excitation positioning technologies. TIVA emphasizes voltage signals, and Obirch emphasizes resistance signals.

[0020] The high-transparency glass 4 is fused quartz glass with a thickness of 1.0±0.05mm, a transmittance of ≥99.5% in the 1064-1550nm waveband, and a thermal expansion coefficient , to ensure that the laser penetrates without distortion.

[0021] The bottom of the glass main plate 1 is respectively provided with a sliding groove 14 and a symmetrical mounting groove 16, the inner cavity of the sliding groove 14 is sleeved with an adjusting block 5, a spring 15 is arranged between the adjusting block 5 and the sliding groove 14, the inner cavity of the mounting groove 16 is threadedly mounted with a top block 6, the adjusting block 5 and the top block 6 are mounted with a wafer 2, the surface of the adjusting block 5 and the middle of the top block 6 protrude the surface of the glass main plate 1, first, the adjusting block 5 is pried, the adjusting block 5 slides in the inner cavity of the sliding groove 14 and presses the spring 15, then the wafer 2 is first mounted at the bottom of the glass main plate 1, the edge of the wafer 2 is first abutted on the top block 6, then the adjusting block 5 is loosened, and the adjusting block 5 is reset under the elastic force of the spring 15, the wafer 2 is clamped.

[0022] The surface of the glass main plate 1 is provided with a ring groove 13, one end of the glass main plate 1 is provided with an air extraction hole 11, the air extraction hole 11 and the inner cavity of the ring groove 13 are communicated with each other, and after the wafer 2 is mounted, the wafer 2 also covers the ring groove 13, wherein the air extraction hole 11 is connected with an external air pump through a pipeline, therefore, when the wafer 2 is clamped at the bottom of the glass main plate 1, negative pressure extraction is carried out through the air pump, the ring groove 13 is extracted through the air extraction hole 11, so that the wafer 2 is adsorbed, therefore, through the adjusting block 5, the spring 15 and the top block 6, self-adaptive clamping can be carried out, damage caused by clamping is avoided, through negative pressure adsorption, fastening force is further improved, and the phenomenon of falling off is avoided.

[0023] Wherein, when the wafer 2 of a single die is detected, because the wafer 2 of a single die cannot be clamped through the adjusting block 5 and the top block 6 like a complete wafer 2, the wafer 2 of a single die is adhered on the high-transparency glass 4 and then detected.

[0024] When the wafer 2 is detected, first, the two ends of the glass main plate 1 are fixedly mounted on a detection support through screws, wherein the detection equipment is provided with detectors above and below, then the adjusting block 5 is pried, the adjusting block 5 slides in the inner cavity of the sliding groove 14 and presses the spring 15, then the wafer 2 is first mounted at the bottom of the glass main plate 1, the edge of the wafer 2 is first abutted on the top block 6, then the adjusting block 5 is loosened, and the adjusting block 5 is reset under the elastic force of the spring 15, the wafer 2 is clamped, the air extraction hole 11 is mounted with an air pipe and connected with an air pump, the air pump is started, the wafer 2 is adsorbed and fixed through the communication of the air extraction hole 11 and the ring groove 13, through the adjusting block 5, the spring 15 and the top block 6, self-adaptive clamping can be carried out, damage caused by clamping is avoided, through negative pressure adsorption, fastening force is further improved, and the phenomenon of falling off is avoided, then the wafer 2 is detected through the detectors above and below of the detection equipment (indium gallium arsenide InGaAs detector detects near-infrared light) to detect the front and back of the wafer 2.

[0025] When the wafer 2 of single dies cannot be used for detection work in clamping, first put the high-transparency glass 4 into the inner cavity of the glass mainboard 1 and abut against the limiting ring 12, then fasten the glass pressing ring 3 in the inner cavity of the glass mainboard 1, then stick the wafer 2 of single dies on the high-transparency glass 4, support through the high-transparency glass 4, first detect the wafer 2 of single dies through the lower probe, after detection, pass the upper probe through the high-transparency glass 4 to detect the wafer 2 of single dies, avoid misjudgment in detection through the light transmittance, flatness and anti-interference of the high-transparency glass 4, and improve the judgment rate.

[0026] It should be noted that the relational terms herein such as first and second and the like are used solely to distinguish one from another entity or action without necessarily requiring or implying any actual relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0027] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, alternatives, and variations can be made in the embodiments without departing from the spirit and scope of the present application as defined by the appended claims and their equivalents.

Claims

1. A high-transmittance glass chuck for chip defect positioning in the EFA field, comprising a glass main board (1), characterized in that: The inner cavity of the glass main plate (1) is integrally extended with a limit ring (12), and the surface of the limit ring (12) is provided with high-transmittance glass (4), and the surface of the high-transmittance glass (4) is provided with a glass pressure ring (3); The bottom of the glass main board (1) is provided with a sliding groove (14) and a symmetrical mounting groove (16), and the inner cavity of the sliding groove (14) is slidably sleeved with an adjusting block (5), and a spring (15) is provided between the adjusting block (5) and the sliding groove (14), and the inner cavity of the mounting groove (16) is threadedly mounted with a top block (6), and a wafer (2) is installed between the adjusting block (5) and the top block (6); An annular groove (13) is provided on the surface of the glass main plate (1), and an air extraction hole (11) is provided at one end of the glass main plate (1), and the air extraction hole (11) and the inner cavity of the annular groove (13) are communicated with each other.

2. The high-transmittance glass chuck for chip defect location in the EFA field according to claim 1, characterized in that: The edge of the high-transmittance glass (4) is bonded to the inner cavity of the glass main board (1).

3. The high-transmittance glass chuck for chip defect location in the EFA field according to claim 1, characterized in that: The glass pressure ring (3) abuts against the high-transmittance glass (4).

4. The high-transmittance glass chuck for chip defect location in the EFA field according to claim 3, characterized in that: The glass pressure ring (3) and the inner cavity of the glass main plate (1) are fastened to each other, and the surfaces of the glass pressure ring (3) and the glass main plate (1) are flush with each other.

5. The high-transmittance glass chuck for chip defect location in the EFA field according to claim 1, characterized in that: The surface of the regulating block (5) and the middle of the top block (6) protrude from the surface of the glass main board (1).

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