Method for reducing ohmic contact resistance of device, device packaging structure and packaging method

Abstract

The invention discloses a method for reducing the ohmic contact resistance of a device, a device packaging structure and a packaging method.The method for reducing the ohmic contact resistance of the device comprises the steps that a laser light source is adopted to continuously irradiate a semiconductor device, and the energy of the laser light source is larger than the forbidden band width of a semiconductor material in the semiconductor device. According to the method for reducing the ohmic contact resistance of the device, the device packaging structure and the packaging method, the semiconductor device can be irradiated by laser, so that photon-generated carriers are generated in the semiconductor device, the contact resistivity is reduced, and the ohmic contact performance of the device is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor devices, and in particular relates to a method for reducing the ohmic contact resistance of a device, a device packaging structure and a packaging method. Background Art

[0002] As the representative of the third generation of semiconductor materials, group III nitrides have been widely used in optoelectronics and microelectronics, so related research has developed rapidly and achieved remarkable results. Compared with the first and second generation semiconductor materials, the third generation of wide bandgap semiconductors have higher breakdown electric fields, electron saturation rates and thermal conductivity, as well as wider band gaps, making them more suitable for manufacturing high-frequency, high-power, radiation-resistant and corrosion-resistant electronic devices, optoelectronic devices and light-emitting devices.

[0003] Ohmic contact refers to a low-impedance contact formed between an electrode and a semiconductor material to achieve good current transfer. For wide-bandgap semiconductors such as gallium nitride (GaN), the study and implementation of ohmic contacts is of great significance because they are widely used in power electronics and optoelectronic devices. Achieving an ideal ohmic contact in GaN devices can not only improve performance, but also affect the overall reliability and life of the device, so it is one of the research focuses.

[0004] Most of the existing solutions are to change the ohmic contact metal layer to reduce the ohmic contact. The reduction in ohmic contact resistance is limited, the process is cumbersome and the cost is high.

[0005] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0006] The object of the present invention is to provide a method for reducing the ohmic contact resistance of a device, a device packaging structure and a packaging method, which can generate photogenerated carriers inside a semiconductor device by laser irradiation, thereby reducing the contact resistivity and improving the ohmic contact performance of the device.

[0007] In order to achieve the above object, a technical solution provided by a specific embodiment of the present invention is as follows:

[0008] A method for reducing the ohmic contact resistance of a device, comprising:

[0009] A laser light source is used to continuously irradiate a semiconductor device, wherein the energy of the laser light source is greater than the bandgap width of the semiconductor material in the semiconductor device.

[0010] In one or more embodiments of the present invention, the semiconductor device includes a semiconductor body and a first electrode and a second electrode formed on the same side of the semiconductor body and spaced apart from each other;

[0011] A laser light source is used to irradiate a gap between a first electrode and a second electrode of the semiconductor device.

[0012] In one or more embodiments of the present invention, an irradiation range of the laser light source completely covers the gap between the first electrode and the second electrode.

[0013] A device packaging structure, comprising:

[0014] A semiconductor device having a semiconductor body and a first electrode and a second electrode formed on the semiconductor body;

[0015] a laser light source, arranged in parallel with the semiconductor device, the laser light source having a first end and a second end, the first end being electrically connected to the first electrode of the semiconductor device, and the second end being electrically connected to the second electrode of the semiconductor device;

[0016] The laser light source is used to irradiate the semiconductor device, and the energy of the laser light source is greater than the bandgap width of the semiconductor material forming the semiconductor body.

[0017] In one or more embodiments of the present invention, the laser light source is disposed on the side where the first electrode and / or the second electrode of the semiconductor device are located, and the laser light emitted by the laser light source can irradiate the peripheral area of ​​the first electrode and / or the second electrode.

[0018] In one or more embodiments of the present invention, the first electrode and the second electrode are formed on the same side of the semiconductor body and are spaced apart from each other.

[0019] In one or more embodiments of the present invention, the laser light source is disposed on the side where the first electrode and the second electrode of the semiconductor device are located, and the laser light emitted by the laser light source can irradiate between the first electrode and the second electrode of the semiconductor device.

[0020] In one or more embodiments of the present invention, an irradiation range of the laser light source completely covers the gap between the first electrode and the second electrode.

[0021] In one or more embodiments of the present invention, the semiconductor device includes a photoconductive switch, a photodetector, a TFT thin film transistor, or a MEMS device; and / or,

[0022] The laser light source comprises a laser diode; and / or,

[0023] The device packaging structure further includes a power supply, the power supply having a positive electrode and a negative electrode, the positive electrode is electrically connected to the first end and the first electrode, and the negative electrode is electrically connected to the second end and the second electrode; and / or,

[0024] The device packaging structure further includes an electric switch, which is arranged on the branch where the laser light source is located, to control the conduction of the branch where the laser light source is located; and / or,

[0025] The device packaging structure also includes a transparent plastic packaging body, and the transparent plastic packaging body covers the laser light source and the semiconductor device.

[0026] A device packaging method, comprising:

[0027] Providing a semiconductor device having a semiconductor body and a first electrode and a second electrode formed on the semiconductor body;

[0028] Providing a laser light source, the laser light source having a first end and a second end, the energy of the laser light source being greater than a bandgap width of a semiconductor material forming the semiconductor body;

[0029] The laser light source is arranged in parallel with the semiconductor device, and the relative position between the laser light source and the semiconductor device is adjusted so that the laser light emitted by the laser light source can irradiate the semiconductor device;

[0030] electrically connecting the first end to the first electrode, and electrically connecting the second end to the second electrode;

[0031] Use transparent plastic sealing material for plastic sealing.

[0032] In one or more embodiments of the present invention, before the step of using a transparent plastic packaging material for plastic packaging, the method further includes:

[0033] Providing a power source having a positive pole and a negative pole;

[0034] The power supply is connected in parallel with the laser light source and the semiconductor device, the positive electrode is electrically connected to the first end and the first electrode, and the negative electrode is electrically connected to the second end and the second electrode.

[0035] Compared with the prior art, the method for reducing the ohmic contact resistance of a device, the device packaging structure and the packaging method of the present invention increase the concentration of photogenerated carriers through laser irradiation, thereby increasing the current, reducing the ohmic contact and reducing the power consumption of the device.

[0036] The device packaging structure and packaging method of the present invention have simple processes, and by connecting a laser light source in parallel with a semiconductor device, laser irradiation with a width greater than the bandgap width is used to significantly reduce the ohmic contact resistivity and thus reduce device power consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0038] Figure 1 A schematic diagram of reducing ohmic contact resistance by laser irradiation in one embodiment of the present invention;

[0039] Figure 2 The measured resistance R diagram of the circular electrodes with different gaps without laser in one embodiment of the present invention;

[0040] Figure 3 The measured resistance R diagram of the circular electrodes with different gaps when a laser with a power of 25 mW is applied in one embodiment of the present invention;

[0041] Figure 4 The R-ln (Rn / R0) curve and its linear fitting without laser in one embodiment of the present invention;

[0042] Figure 5 The R-ln (Rn / R0) curve and its linear fitting of a 25 mW laser power in one embodiment of the present invention;

[0043] Figure 6 is the relationship between the ohmic contact resistivity and the laser power in one embodiment of the present invention;

[0044] Figure 7 Schematic diagram of a device packaging structure in one embodiment of the present invention. DETAILED DESCRIPTION

[0045] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0046] As mentioned in the background art, the method of reducing ohmic contact resistance in the prior art is usually to change the ohmic contact metal layer.

[0047] For example, the invention patent with publication number CN113990993A discloses a light-emitting diode epitaxial wafer for reducing ohmic contact resistance and a manufacturing method thereof, wherein the light-emitting diode epitaxial wafer comprises a porous gallium nitride substrate, and an undoped GaN layer, an N-type waveguide layer, a multi-quantum well layer, a composite P-type waveguide layer and a P-type contact layer stacked in sequence on the substrate, wherein the P-type contact layer comprises a first sublayer, a second sublayer and a third sublayer stacked in sequence, wherein the first sublayer and the third sublayer are both Mg-doped GaN layers, the second sublayer is an undoped GaN layer, and a plurality of nanoparticles are evenly distributed on the side of the second sublayer in contact with the third sublayer. The light-emitting diode epitaxial wafer can reduce the ohmic contact resistance of the P-type contact layer and improve the luminous efficiency of the LED.

[0048] For example, the invention patent with publication number CN118315421A discloses a low-resistance GaN device structure and its preparation method, including a substrate, a GaN buffer layer, a GaN channel layer, a superlattice barrier layer, an ohmic contact electrode and a passivation layer stacked in sequence, wherein the superlattice barrier layer adopts a GaN / AlN superlattice structure, and the superlattice barrier layer and the GaN channel layer produce a polarization effect to form a high-density two-dimensional electron gas 2DEG, thereby realizing a GaN device with low on-resistance, and an ion implantation passivation layer is provided between the superlattice barrier layer and the ohmic contact electrode, and ions are implanted into the superlattice barrier layer through the ion implantation passivation layer, so that it is connected to the high-density two-dimensional electron gas 2DEG and activated by high-temperature annealing, thereby reducing the ohmic contact resistance. The low-resistance GaN device prepared by this invention has the advantages of low resistivity, simple process, small material damage, and good ohmic contact morphology.

[0049] For example, the invention patent with the publication number CN118315421A discloses a method for manufacturing ohmic contacts of gallium nitride devices, including a substrate layer, a buffer layer, a gallium nitride channel layer, an aluminum nitride isolation layer, an aluminum gallium nitride barrier layer, and a cap layer, on which a window is sequentially epitaxially grown, through cleaning, photolithography and etching processes, a window is opened in the cap layer to the aluminum gallium nitride barrier layer, and source and drain metals are deposited by an electron beam evaporation table or an ion sputtering machine, the drain and source metals are sequentially composed of alloyed contact metals, barrier layer metals and anti-oxidation protection layer metals, the alloyed contact metals are a multilayer metal alloy structure of Sc / Ti / Al, the drain and source metals are annealed at high temperature in a nitrogen atmosphere by a rapid annealing furnace, and AlGaN is alloyed with Sc / Ti / Al to obtain ohmic contacts. The ohmic contact proposed in this invention can reduce the ohmic contact resistance by 20% to 50% on the basis of the existing process, reduce the ohmic contact annealing temperature by 50-100 degrees, and improve the surface flatness, thereby correspondingly improving the stability and reliability of the ohmic contact, as well as the device operating current and output power.

[0050] However, the above method has limited effect on reducing the ohmic contact resistance and the process is complicated and costly.

[0051] Based on this, the present invention provides a method for reducing the ohmic contact resistance of a device, a device packaging structure and a packaging method, by irradiating a semiconductor device with a laser to generate photogenerated carriers inside the semiconductor device, thereby reducing the contact resistivity and improving the ohmic contact performance of the device.

[0052] The method of reducing the ohmic contact resistance of a device of the present invention comprises using a laser light source to continuously irradiate the semiconductor device, wherein the energy of the laser light source is greater than the bandgap width of the semiconductor material in the semiconductor device.

[0053] The choice of laser light source wavelength is related to the semiconductor material forming the semiconductor device. For semiconductor materials with a bandgap width of Eg, the selected laser light source wavelength should satisfy h*c / λ>Eg, where h is Planck's constant, c is the speed of light, and λ is the laser wavelength.

[0054] Preferably, the semiconductor device of the present invention comprises a semiconductor body and a first electrode and a second electrode formed on the same side of the semiconductor body and spaced apart. A laser light source is used to irradiate between the first electrode and the second electrode of the semiconductor device, and the irradiation range of the laser light source completely covers the gap between the first electrode and the second electrode. More preferably, in the semiconductor device of the present invention, the first electrode is a circular electrode, and the second electrode is a central circular electrode located in the area surrounded by the circular electrode.

[0055] It can be understood that in another embodiment, the first electrode and the second electrode in the semiconductor device can also be formed on different sides of the semiconductor body, respectively. In this case, the laser light source can be irradiated on the semiconductor body on the side where the first electrode is located, or on the semiconductor body on the side where the second electrode is located, or on the side area of ​​the semiconductor body.

[0056] The semiconductor device may include a photoconductive switch, a photodetector, a TFT thin film transistor, or a MEMS device. The laser light source is preferably a laser diode.

[0057] refer to Figure 1 As shown, Figure 1 A schematic diagram of reducing ohmic contact resistance by laser irradiation is provided, wherein a photocurrent testing system is disclosed for testing the current of an electrode at different light powers when a laser light source irradiates a semiconductor device. Figure 1 The system shown in can be used on a semiconductor device A having a circular electrode.

[0058] The semiconductor device A with annular electrodes described in the present invention refers to two electrodes of the semiconductor device A, one of which is an annular electrode and the other is a central circle electrode located in the area surrounded by the annular electrodes.

[0059] Exemplarily, the system includes a laser 11, and an attenuation plate 12, a concave lens 13 and a reflector 14 arranged in sequence along the optical path of the laser 11. A power probe 15 is arranged on the optical path between the attenuation plate 12 and the concave lens 13, and a power detector 16 is connected to the power probe 15.

[0060] The laser light emitted by the laser 11 is detected by the power sensor 15 after passing through the attenuation plate 12, and the energy is displayed on the power detector 16. The energy of the laser light can be changed by rotating the attenuation plate 12. The laser spot is magnified by the concave lens 13 and irradiated to the electrode area of ​​the semiconductor device A through the reflector 14, and completely covers the gap between the electrodes. The source meter 17 can provide power and display the current reading. A scanning voltage of -10V to 10V is applied to test the current of the electrode under different optical powers.

[0061] The laser power is changed by adjusting the attenuation sheet 12, and the laser power is measured by the power detector 16. The ohmic contacts under different laser powers are fitted according to different laser powers.

[0062] The power sensor 15 is not used to transmit laser light and needs to be removed after measuring the laser power.

[0063] One of the two needles of the source meter 17 is placed on the circular electrode, and the other is placed on the layer structure of the semiconductor material outside the circular electrode. The laser spot covers the central circular electrode and the gap between the central circular electrode and the circular electrode.

[0064] Taking semiconductor device A as a GaN device as an example, for semiconductor devices based on GaN material and having annular electrodes, the present invention tests the IV curve of laser application under different inter-electrode gaps (the gap between the annular electrode and the center circle electrode), thereby fitting a curve of quantitative change of contact resistivity with optical power.

[0065] in, Figure 2 The measured resistance R diagram of the ring electrode with each different gap without laser, the horizontal axis is voltage, and the vertical axis is current; Figure 3 The measured resistance R graph of the circular electrode with different gaps under 25mW laser power, with voltage on the abscissa and current on the ordinate. The inner diameter of the circular electrode is 300um, and the difference between the outer diameter and the inner diameter is 5um, 10um, 15um, 20um, 25um, 30um, 35um, and 40um respectively. Figure 2 In the upper right corner display area, each line from top to bottom represents the difference between the inner and outer diameters of 5um, 10um, 15um, 20um, 25um, 35um, 30um, and 40um; Figure 2In the lower left corner display area, each line from top to bottom represents the difference between the inner and outer diameters of 40um, 30um, 35um, 25um, 20um, 15um, 10um, and 5um. Figure 3 In the upper right corner display area, each line from top to bottom represents the difference between the inner and outer diameters of 5um, 10um, 15um, 20um, 25um, 35um, 30um, and 40um; Figure 3 In the lower left corner display area, each line from top to bottom represents the difference between the inner and outer diameters of 40um, 30um, 35um, 25um, 20um, 15um, 10um, and 5um. Figure 2 and Figure 3 It can be seen that after laser irradiation, the current of the GaN device increases and the power consumption decreases.

[0066] The resistance R is composed of the contact resistance on both sides of the ring and the bulk resistance of the semiconductor material, which can be expressed as

[0067] R = Rsh / 2π*[ln(Rn / R0)+L(1 / Rn+1 / R0)](1)

[0068] Where Rsh is the sheet resistance of the semiconductor material, and L is the transmission distance. Its relationship with the sheet resistance and contact resistivity is: ρc = L2Rsh (2)

[0069] With ln(Rn / R0) as the horizontal coordinate and the measured resistance R as the vertical coordinate, a scatter plot of 8 points can be made. Since Rn-R0 is very small, it can be approximately considered that Rn=R0. Therefore, in theory, the curve of R-ln(Rn / R0) is a straight line. By fitting them with the least squares method, a straight line describing the relationship between R-ln(Rn / R0) can be obtained. Therefore, we can get Figure 4 and Figure 5 .

[0070] Figure 4 is the R-ln (Rn / R0) curve without laser and its linear fitting; Figure 5 The R-ln(Rn / R0) curve and its linear fit of the laser power of 25mW. The slope of the straight line is Rsh / 2π, and the intercept at the coordinate ln(Rn / R0)=0 is RshL / πR0, so the transmission distance L is obtained, and finally the contact resistivity is calculated according to formula (2). So we can get Figure 6 , Figure 6 In the figure, the horizontal axis is the laser power and the vertical axis is the resistivity. Figure 6 It can be seen that with the increase of laser power, the contact resistivity ρc of GaN devices continues to decrease. When the laser power reaches 25mW, the contact resistivity decreases by 8000 times.

[0071] Based on this, reference Figure 7 As shown, the present invention further provides a device packaging structure, including a semiconductor device 20 and a laser light source 30. The laser light source 30 is arranged in parallel with the semiconductor device 20. The laser light source 30 is used to irradiate the semiconductor device 20.

[0072] The semiconductor device 20 includes a semiconductor body 21 and a first electrode 22 and a second electrode 23 formed on the semiconductor body 21. The first electrode 22 and the second electrode 23 may be electrodes on different surfaces, or electrodes on the same surface or on the same side. The first electrode 22 and the second electrode 23 may be a circular ring electrode and a center circle electrode or two square electrodes. The laser light source 30 includes a first end 31 and a second end 32, wherein the first end 31 is electrically connected to the first electrode 22 of the semiconductor device 20, and the second end 32 is electrically connected to the second electrode 23 of the semiconductor device 20.

[0073] When the first electrode 22 and the second electrode 23 are skew electrodes, the laser light source 30 can be disposed on the side where the first electrode 22 and / or the second electrode 23 of the semiconductor device 20 are located, and the laser light source 30 can emit laser energy to the peripheral area of ​​the first electrode 22 and / or the second electrode 23; or, the laser light source 30 can be disposed on the peripheral side of the semiconductor device 20, and the laser light emitted by the laser light source 30 can emit laser energy to the semiconductor body 21.

[0074] Preferably, the first electrode 22 and the second electrode 23 are electrodes on the same surface or on the same side, and the first electrode 22 and the second electrode 23 are formed on the same side of the semiconductor body 21 and are arranged at intervals. The laser light source 30 is arranged on the side where the first electrode 22 and the second electrode 23 of the semiconductor device 20 are located, and the laser light source 30 emits the laser energy to irradiate between the first electrode 22 and the second electrode 23 of the semiconductor device 20. And preferably, the irradiation range of the laser light source 30 completely covers the gap between the first electrode 22 and the second electrode 23.

[0075] The semiconductor device 20 may include a photoconductive switch, a photodetector, a TFT thin film transistor, or a MEMS device. The semiconductor material in the semiconductor device 20 is preferably a third generation semiconductor material, such as GaN. The laser light source 30 may include a laser diode.

[0076] Exemplarily, the semiconductor device 20 is a GaN device, and the laser light source 30 is a laser diode. The laser diode emits laser light to illuminate the GaN device, and photogenerated carriers are generated inside the GaN device, thereby reducing the contact resistivity.

[0077] In a preferred embodiment, the electrodes of the GaN device are a circular ring electrode and a central circle electrode arranged on the same surface, and the laser diode is arranged above the side of the GaN device where the electrode is arranged, and the laser diode is arranged above the gap between the two electrodes of the GaN device to ensure that the laser can irradiate the electrode gap, and at the same time, the laser spot needs to completely cover the entire area of ​​the electrode gap to ensure that the utilization rate of the laser energy is maximized. When necessary, the laser diode can be turned on to irradiate and reduce the contact resistivity.

[0078] There are several ways to fix the laser light source 30 above the semiconductor device 20:

[0079] (1) Adhesive: A suitable conductive or non-conductive adhesive, such as epoxy resin, can be used to fix the laser light source 30 on top of the semiconductor device 20. It is necessary to ensure that the thermal conductivity of the adhesive is good enough to dissipate heat faster.

[0080] (2) Mechanical fixation: Use a micro-fixture or bracket to fix the laser light source 30. When designing the fixture, it is necessary to consider the alignment accuracy and the effect of temperature changes on the material size.

[0081] (3) Welding: If the contact surfaces of the laser light source 30 and the semiconductor device 20 are suitable, they can be fixed by welding to ensure firm contact.

[0082] (4) Hot pressing: For some high-power applications, hot pressing technology can be used to press the laser light source 30 onto the semiconductor device 20 to achieve good thermal contact and mechanical fixation.

[0083] (5) Optical alignment: Ensure that the light-emitting end of the laser light source 30 is aligned with the receiving end of the semiconductor device 20 (which can be the semiconductor body, preferably the gap between electrodes). Optical alignment methods can be used.

[0084] Furthermore, the device packaging structure also includes a transparent plastic package (not shown). The transparent plastic package is at least disposed between the laser light source 30 and the semiconductor device 20. The transparent plastic package, such as polymer or glass, can ensure that the laser beam passes smoothly and irradiates the semiconductor device 20.

[0085] The selection of laser wavelength is related to the material of the semiconductor device. For a semiconductor material with a bandgap width of Eg, the selected laser wavelength should satisfy h*c / λ>Eg, where h is Planck's constant, c is the speed of light, and λ is the laser wavelength. Therefore, the energy of the laser light source 30 should be greater than the bandgap width of the semiconductor material forming the semiconductor body 21.

[0086] For semiconductor devices based on GaN materials, the bandgap width of GaN is 3.4eV, so it is reasonable to select a laser light source with a wavelength of 360nm. The present invention has no requirements for the irradiation time of the laser light source, because the reaction is almost transient. Once the irradiation is carried out, the contact resistivity decreases immediately; when the irradiation is turned off, the contact resistivity recovers immediately.

[0087] Furthermore, the device packaging structure may also include an electric switch 40 , which is disposed on the branch where the laser light source 30 is located, to control the conduction of the branch where the laser light source 30 is located.

[0088] Furthermore, the device packaging structure may further include a power supply 50 , the power supply 50 having a positive electrode and a negative electrode, the positive electrode being electrically connected to the first end, the first electrode 22 , and the negative electrode being electrically connected to the second end, the second electrode 23 .

[0089] The present invention also provides a packaging method for the above device packaging structure, comprising:

[0090] S1 , providing a semiconductor device, wherein the semiconductor device has a semiconductor body and a first electrode and a second electrode formed on the semiconductor body.

[0091] S2, providing a laser light source, wherein the laser light source has a first end and a second end, and the energy of the laser light source is greater than the bandgap width of the semiconductor material forming the semiconductor body.

[0092] S3, setting the laser light source and the semiconductor device in parallel, and adjusting the relative position between the laser light source and the semiconductor device so that the laser light emitted by the laser light source can irradiate the semiconductor device.

[0093] In this step S3, in order for the semiconductor device to effectively receive the light emitted by the laser light source, factors such as the laser spot size, the laser emission angle, and the refractive index of the semiconductor material need to be considered. After determination, a fine-tuning device is used to accurately align the laser light source and the semiconductor device to improve light transmission efficiency. The semiconductor device and the laser light source are fixed together using thermal conductive glue or other suitable adhesive materials to ensure that they will not move during use.

[0094] Preferably, the relative position between the laser light source and the semiconductor device is adjusted so that the laser light emitted by the laser light source can irradiate the location of the electrode of the semiconductor device and the laser spot range is larger than the electrode size.

[0095] More preferably, on a semiconductor device with electrodes on the same surface, the laser spot range completely covers the spacing area between adjacent electrodes.

[0096] S4, electrically connecting the first end to the first electrode, and electrically connecting the second end to the second electrode.

[0097] S5, providing a power supply having a positive electrode and a negative electrode; setting the power supply in parallel with the laser light source and the semiconductor device, with the positive electrode electrically connected to the first end and the first electrode, and the negative electrode electrically connected to the second end and the second electrode.

[0098] Specifically, the power supply and drive circuit of the laser light source are connected to the corresponding pins to ensure that the current and voltage meet the requirements of the laser light source. A protection circuit can be added as needed to prevent overcurrent and other situations.

[0099] S6, plastic sealing with transparent plastic sealing material.

[0100] S7, after packaging is completed, functional testing is performed to ensure that the laser light source can emit light stably and that the semiconductor device functions normally.

[0101] It is understandable that after the above steps are completed, dust-proof, moisture-proof and other protective measures can be added as needed to extend the service life of the equipment.

[0102] Furthermore, other factors may also be considered depending on the requirements of specific applications, such as heat dissipation management, vibration resistance, size constraints, etc.

[0103] In the device packaging structure of the present invention, the laser light source and the semiconductor device are electrically connected, and the laser light source and the semiconductor device are connected in parallel to the same power supply, and the laser light source and the semiconductor device share positive and negative electrodes. When the semiconductor device needs to be turned on or turned on, the laser light source is turned on to irradiate the semiconductor device, and the contact resistivity is reduced by 8000 times in a very short time scale (nanosecond level).

[0104] Compared with the prior art, the method for reducing the ohmic contact resistance of a device, the device packaging structure and the packaging method of the present invention increase the concentration of photogenerated carriers through laser irradiation, thereby increasing the current, reducing the ohmic contact and reducing the power consumption of the device.

[0105] The device packaging structure and packaging method of the present invention have simple processes, and by connecting a laser light source in parallel with a semiconductor device, laser irradiation with a width greater than the bandgap width is used to significantly reduce the ohmic contact resistivity and thus reduce device power consumption.

[0106] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0107] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A method for reducing the ohmic contact resistance of a device, characterized in that: include: A laser light source is used to continuously irradiate a semiconductor device, wherein the energy of the laser light source is greater than the bandgap width of the semiconductor material in the semiconductor device.

2. The method for reducing the ohmic contact resistance of a device according to claim 1, characterized in that: The semiconductor device comprises a semiconductor body and a first electrode and a second electrode formed on the same side of the semiconductor body and spaced apart from each other; A laser light source is used to irradiate a gap between a first electrode and a second electrode of the semiconductor device.

3. The method for reducing the ohmic contact resistance of a device according to claim 2, characterized in that: The irradiation range of the laser light source completely covers the gap between the first electrode and the second electrode.

4. A device packaging structure, characterized in that: include: A semiconductor device having a semiconductor body and a first electrode and a second electrode formed on the semiconductor body; a laser light source, arranged in parallel with the semiconductor device, the laser light source having a first end and a second end, the first end being electrically connected to the first electrode of the semiconductor device, and the second end being electrically connected to the second electrode of the semiconductor device; The laser light source is used to irradiate the semiconductor device, and the energy of the laser light source is greater than the bandgap width of the semiconductor material forming the semiconductor body.

5. The device packaging structure according to claim 4, characterized in that: The laser light source is arranged on the side where the first electrode and / or the second electrode of the semiconductor device are located, and the laser light emitted by the laser light source can irradiate the peripheral area of ​​the first electrode and / or the second electrode.

6. The device packaging structure according to claim 4, characterized in that: The first electrode and the second electrode are formed on the same side of the semiconductor body and are spaced apart from each other.

7. The device packaging structure according to claim 6, characterized in that: The laser light source is arranged on the side where the first electrode and the second electrode of the semiconductor device are located, and the laser light emitted by the laser light source can irradiate between the first electrode and the second electrode of the semiconductor device.

8. The device packaging structure according to claim 7, characterized in that: The irradiation range of the laser light source completely covers the gap between the first electrode and the second electrode.

9. The device packaging structure according to claim 4, characterized in that: The semiconductor device includes a photoconductive switch, a photodetector, a TFT thin film transistor, or a MEMS device; and / or, The laser light source comprises a laser diode; and / or, The device packaging structure further includes a power supply, the power supply having a positive electrode and a negative electrode, the positive electrode is electrically connected to the first end and the first electrode, and the negative electrode is electrically connected to the second end and the second electrode; and / or, The device packaging structure also includes an electric switch, which is arranged on the branch where the laser light source is located, and controls the conduction of the branch where the laser light source is located; and / or, The device packaging structure further includes a transparent plastic package body, and the transparent plastic package body covers the laser light source and the semiconductor device.

10. A device packaging method, characterized in that: include: Providing a semiconductor device having a semiconductor body and a first electrode and a second electrode formed on the semiconductor body; Providing a laser light source, the laser light source having a first end and a second end, the energy of the laser light source being greater than a bandgap width of a semiconductor material forming the semiconductor body; The laser light source is arranged in parallel with the semiconductor device, and the relative position between the laser light source and the semiconductor device is adjusted so that the laser light emitted by the laser light source can irradiate the semiconductor device; electrically connecting the first end to the first electrode, and electrically connecting the second end to the second electrode; Use transparent plastic sealing material for plastic sealing.

11. The device packaging method according to claim 10, characterized in that: Before the step of using the transparent plastic sealing material for plastic sealing, the step also includes: Providing a power source having a positive pole and a negative pole; The power supply is connected in parallel with the laser light source and the semiconductor device, the positive electrode is electrically connected to the first end and the first electrode, and the negative electrode is electrically connected to the second end and the second electrode.

Images