JP6930412B2 - Semiconductor devices and their manufacturing methods - Google Patents

Description

The present invention relates to a semiconductor device including a semiconductor chip and a mold resin for encapsulating a part thereof, and a method for manufacturing the same.

Conventionally, in this type of semiconductor device, the resin material covering the protruding portion is partially removed by laser irradiation or the like for the purpose of stress relaxation and removal of resin burrs in the protruding portion of the semiconductor chip protruding from the mold resin. Is being done. Examples of such a semiconductor device and a method for manufacturing the same include those described in Patent Document 1.

The semiconductor device described in Patent Document 1 is sealed in a mold resin together with a semiconductor chip including a sensor unit that outputs a signal according to a physical quantity, a mold resin, and a part of the semiconductor chip, and controls the semiconductor chip. It is provided with a circuit chip that performs the above. This semiconductor device has a structure in which a part of the semiconductor chip is covered with the mold resin and the rest is a protruding portion protruding from the mold resin, and the semiconductor chip is cantilevered by the mold resin.

Here, in this type of semiconductor device, with the formation of the mold resin, resin burrs are formed in the protruding portion of the semiconductor chip, and the stress due to the difference in linear expansion coefficient between the semiconductor chip and the mold resin is concentrated. Or something. As a countermeasure against these problems, the resin burr formed on the protruding portion of the semiconductor chip and the resin material covering the protruding portion are removed by laser irradiation or the like.

Further, in this type of semiconductor device, the mold resin is configured to contain a filler such as _{SiO 2} for the purpose of reducing the difference in linear expansion coefficient between the semiconductor chip and the mold resin and relaxing the stress at these interfaces. There is. When the mold resin is configured to contain a filler in this way, when removing the resin burrs made of such a resin material, the filler is transmitted through the laser in laser irradiation and remains without being removed, or the filler. Can reattach and contaminate the surface.

In the semiconductor device described in Patent Document 1, in order to prevent the above-mentioned problems, a mold resin containing a filler is formed after covering a portion where resin burrs may occur with a filler-less resin containing no filler in advance. .. Then, the filler-less resin is irradiated with a laser to remove the filler-less resin, thereby obtaining this semiconductor device. Therefore, even if the mold resin is configured to contain a filler, the semiconductor device and the manufacturing method thereof are obtained in which the above-mentioned problems caused by the filler are suppressed.

Japanese Patent No. 6090041

By the way, in this type of semiconductor device, the semiconductor chip may have a serial number, a wiring electrode, or the like formed of a material such as Al on the surface of a protruding portion. In such a case, if the laser irradiation is performed in the vicinity of the protruding portion of the semiconductor chip, the material constituting the serial number or the like absorbs the laser and generates heat, which may damage a part of the laser. However, the semiconductor device described in Patent Document 1 has a configuration in which damage to the protruding portion due to such laser irradiation cannot be prevented.

Further, in the manufacturing process of this semiconductor device, in addition to the resin material containing the filler, a filler-less resin to be arranged in the region to be irradiated with the laser is separately required, which increases the cost.

Further, when the step of using the filler-less resin is adopted, when the filler-less resin is a hard material, the pressure for molding the mold resin is excessively applied to the semiconductor chip through the hard filler-less resin at the time of forming the mold resin. Will be transmitted to. In such a case, due to the influence of the excessively transmitted pressure, it may remain as an internal stress in the semiconductor chip, and the reliability may be lowered.

The present invention has been made in view of the above points, and is a semiconductor device in which damage on the surface of the protruding portion of the semiconductor chip is suppressed when the resin material is removed from the protruding portion from the mold resin. It is an object of the present invention to provide a manufacturing method. Another object of the present invention is to provide a semiconductor device having a structure in which the mold resin contains a filler, but which can be easily manufactured without using a separate fillerless resin, and a method for manufacturing the same.

In order to achieve the above object, the semiconductor device according to claim 1 includes a semiconductor chip (1) having a sensor unit (31) that outputs a signal according to a physical quantity, and a mold resin (1) that covers a part of the semiconductor chip. 6) and. In such a configuration, the portion of the semiconductor chip protruding from the mold resin is regarded as the protruding portion (3), and the exposed portion (3a) of the protruding portion exposed from the mold resin is the portion of the mold resin covering the protruding portion. The laser removal region includes the laser removal region exposed from the mold resin by being partially irradiated with the laser and removed, and the laser removal region has a laser absorption rate in the wavelength range of 1.5 μm or more and 6.0 μm or less. It is a region composed of the laser low absorption material (7) which is 45% or less.

As a result, a part of the semiconductor chip protruding from the mold resin, which is exposed from the mold resin by laser irradiation, is made of a laser low absorption material, and the semiconductor chip is caused by laser absorption. It is a semiconductor device in which damage is suppressed.

The semiconductor device according to claim 5 includes a semiconductor chip (1) having a sensor unit (31) that outputs a signal according to a physical quantity, and a mold resin (6) that covers a part of the semiconductor chip. In such a configuration, the portion of the semiconductor chip that protrudes from the mold resin is used as the protruding portion (3), and the protruding portion has a coating portion (3b) that is at least partially covered with the mold resin. , Filler (62) is contained, the normal direction with respect to one surface of the semiconductor chip on which the coating portion is formed is the one-side normal direction, and the portion of the mold resin covering the coating portion is designated as the thinning portion (6b). , The filler has a particle size larger than the thickness in the one-sided normal direction of the thinned portion, and is arranged in a portion different from the thinned portion.

As a result, while the mold resin is composed of the resin material containing the filler, the mold resin has a thinned portion as a filler-less portion, and the structure is such that defects caused by the filler in laser processing are suppressed. It becomes a semiconductor device.

The method for manufacturing a semiconductor device according to claim 6 is to prepare a semiconductor chip (1) having a sensor unit (31) that outputs a signal according to a physical quantity, and a mold resin (1) that covers at least a part of the semiconductor chip. To prepare a mold (200) to be used for forming 6), to set a semiconductor chip in the mold, to pour a resin material constituting the mold resin and cure it to form a mold resin. After forming the mold resin, a part of the protruding portion (3) protruding from the mold resin of the semiconductor chip is irradiated with a laser to form an exposed portion (3a) that exposes the part from the mold resin. And, including. In preparing a semiconductor chip in such a method, a laser low absorption material (7) having a laser absorption rate of 45% or less is covered by a portion of the mold resin that is irradiated and removed by the laser. Prepare a semiconductor chip in which is arranged.

As a result, when a part of the mold resin covering a part of the protruding portion protruding from the mold resin of the semiconductor chip is removed by laser irradiation, the part of the semiconductor chip covered with the mold resin is removed. It is a semiconductor chip made of a laser low absorption material. Therefore, even if a part of the mold resin is irradiated with the laser and removed, the part of the semiconductor chip covered with the mold resin is made of the laser low absorption material, so that the laser Absorption is suppressed. Therefore, when a part of the mold resin is removed by laser irradiation, it is possible to manufacture a semiconductor device in which damage to the semiconductor chip is suppressed.

The method for manufacturing a semiconductor device according to claim 9 is to prepare a semiconductor chip (1) having a sensor unit (31) that outputs a signal according to a physical quantity, and a mold resin (1) that covers at least a part of the semiconductor chip. 6) Including preparing a mold (200) to be used for forming. In such a manufacturing method, in forming a mold resin by setting a semiconductor chip in a mold and pouring a resin material constituting the mold resin and curing the mold resin, a filler (62) is used in forming the mold resin. ) Is used, and the portion of the semiconductor chip that protrudes from the mold resin after the formation of the mold resin is used as the protrusion (3). Prepare a mold in which the gap between the plastic part and the part to be the plastic is smaller than the particle size of the filler.

As a result, it is possible to form a mold resin that is partially filled-less while forming a mold resin using a resin material containing a filler, and there is a problem caused by the filler during laser processing. Suppressed semiconductor devices can be manufactured.

The reference numerals in parentheses of the above means indicate an example of the correspondence with the specific means described in the embodiment described later.

It is sectional drawing which shows the semiconductor device of 1st Embodiment. FIG. 5 is a top layout view showing a protruding portion of a semiconductor chip and its vicinity in the semiconductor device of the first embodiment. It is a figure which shows the laser irradiation process in the manufacturing process of the semiconductor device of 1st Embodiment. It is a figure which shows an example of the laser irradiation in the laser irradiation process which follows FIG. 3A. It is a figure which shows the absorption rate of Si with respect to the wavelength. It is a figure which shows the absorption rate _{of SiO 2} with respect to a wavelength. It is a figure which shows the absorption rate _{of Si 3} N ₄ with respect to a wavelength. It is a figure which shows the absorption rate of the epoxy resin-based resin material with respect to the wavelength. It is sectional drawing which shows the semiconductor device of 2nd Embodiment. It is an enlarged cross-sectional view of the region shown by the broken line in FIG. It is a figure which shows an example of the particle size distribution of a filler. It is a figure which shows the mold resin molding in the manufacturing process of the semiconductor device of 2nd Embodiment. It is a figure which shows the mold resin molding among the manufacturing process of the semiconductor device in another embodiment. It is a figure which shows the molding resin molding in the conventional semiconductor device using a mold and a film.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each of the following embodiments, parts that are the same or equal to each other will be described with the same reference numerals.

(First Embodiment)
The semiconductor device S1 of the first embodiment will be described with reference to FIGS. 1 to 3 by taking the case where it is applied as a pressure sensor as an example.

FIG. 2 shows the top layout of the semiconductor chip 1 shown in FIG. 1 when viewed from the normal direction (hereinafter referred to as “one-side normal direction”) with respect to one surface 1a, and also shows the outer shell of the sensor unit 31 at one point. The chain line shows the outer shell of the supported portion 2 covered with the mold resin 6 by a broken line. Further, in FIG. 2, in order to make the configuration easy to understand, the laser low absorption material described later is omitted while omitting the portion of the semiconductor chip 1 and the mold resin 6 that covers a part of the semiconductor chip 1 and other regions other than the vicinity thereof. Of the sevens, only those separately arranged on the second substrate 12 are shown.

In the semiconductor device S1 of the present embodiment, for example, as shown in FIG. 1, a semiconductor chip 1 having a sensor unit 31 that outputs a signal corresponding to a physical quantity, a wire 4, a lead frame 5, and a mold resin 6 are provided. Be prepared. In the semiconductor device S1, the sensor unit 31 outputs an electric signal according to the physical quantity, and the electric signal is the pad unit 123, the wire 4, and the lead frame 5 described later via a circuit wiring (not shown) formed on the semiconductor chip 1. It is configured to be transmitted to the outside in order. The semiconductor device S1 of the present embodiment is applied as, for example, a pressure sensor for measuring the pressure of intake air, engine oil, or the like in a vehicle such as an automobile.

The semiconductor device S1 has a configuration in which a semiconductor element (not shown) for controlling an electric signal output by the sensor unit 31 is further arranged in the mold resin 6 and arranged between the semiconductor chip 1 and the lead frame 5. You may. As described above, the configuration in the transmission path of the electric signal output from the sensor unit 31 may be appropriately changed.

As shown in FIG. 1, the semiconductor chip 1 includes, for example, a flat plate-shaped first substrate 11 and a second substrate 12 mainly made of a semiconductor material such as Si, and these substrates 11 and 12 are It is said that they are pasted together. As shown in FIG. 1, a part of the semiconductor chip 1 is mounted on the lead frame 5 and fixed by an adhesive such as silver paste or epoxy (not shown). In the present embodiment, the semiconductor chip 1 is in a state of being partially covered and supported by the mold resin 6, that is, a cantilever state, as shown in FIG.

In the following description, as shown in FIG. 1, the portion of the semiconductor chip 1 that is thickly covered and supported by the mold resin 6 is referred to as the “supported portion 2”, and the rest of the semiconductor chip 1, that is, the mold. The portion protruding from the resin 6 to the opposite side of the supported portion 2 is referred to as a “protruding portion 3”. Further, as shown in FIG. 2, a portion of the mold resin 6 that covers a portion different from the protrusion 3 is covered with a “support portion 6a”, and a portion of the mold resin 6 is covered with a thickness thinner than that of the support portion 6a. Is referred to as "thinning portion 6b". Further, as shown in FIG. 2, the portion of the protruding portion 3 exposed from the mold resin 6 is the “exposed portion 3a”, and the portion of the protruding portion 3 covered by the thinned portion 6b is the “covered portion 3b”. It is called.

In the present embodiment, as shown in FIG. 2, the semiconductor chip 1 absorbs a laser in a manufacturing process described later on a part of the protruding portion 3 on one surface 1a on the opposite side of the surface on which the sensor portion 31 is formed. A laser low absorption material 7 having a rate of 45% or less is arranged. In other words, from the formation of the mold resin 6 in the manufacturing process described later to the laser processing, a region of the semiconductor chip 1 covered with a part of the mold resin 6 removed by the laser processing (hereinafter, “laser removal region”). ”) Is mainly composed of the laser low absorption material 7.

The phrase "the laser removal region is mainly composed of the laser low absorption material 7" is not limited to the case where the laser removal region is composed of only the laser low absorption material 7. In addition to 7, it is meant to include the case where unavoidable impurities and foreign substances are contained.

The laser low absorption material 7 is, for example, a material having an absorption rate of 45% or less at a wavelength of 1.5 μm to 6 μm of a laser used for laser processing described later, specifically, Si, SiO ₂ , SiC, sapphire, GaN, and GaAs. And InP. The laser low absorption material 7 is used not only as the first substrate 11 and the second substrate 12 constituting the semiconductor chip 1, but also as a material separately arranged on the second substrate 12 as shown in FIG. Used. In the latter case, the laser low absorption material 7 covers a serial number, an alignment mark, etc. (not shown) formed of a material such as Al on one surface 1a of the protrusion 3 of the semiconductor chip 1, and protects them. Used as a membrane.

The surface of the semiconductor chip 1 is not irradiated with a laser during laser processing, and the portion covered with the mold resin 6 is covered with a material having high adhesion to the mold resin 6 or a material having a stress relaxation effect. It may be broken. Examples of the material having high adhesion to the mold resin 6 include Si ₃ N ₄ and PIQ (Polyimideiso-indoloquinazo-linedione). _{Specifically, Si 3} N ₄ and PIQ are arranged on a part or all of the surfaces of the supported portion 2 and the covering portion 3b of the semiconductor chip 1, and the structure is such that the adhesion with the mold resin 6 is enhanced. You may.

Further, the semiconductor chip 1 has an arbitrary semiconductor chip configuration except that the laser removal region is composed of the laser low absorption material 7, and even if the configuration other than the laser low absorption material 7 is appropriately changed. good.

As shown in FIG. 1, the first substrate 11 is attached to the second substrate 12 in a state where one surface 11a of the first substrate 11 faces the one surface 12a side of the second substrate 12. The first substrate 11 has a first recess 111 recessed toward the one surface 11a side on the surface opposite to the one surface 11a, and has a thin portion 112 thinned by the formation of the first recess 111. The first substrate 11 is formed with a circuit wiring (not shown) extending from the thin portion 112 to the supported portion 2 side and a gauge resistor electrically connected thereto on the one surface 11a side. This gauge resistance is formed on, for example, the thin-walled portion 112, deforms with the deformation of the thin-walled portion 112, and its resistance value changes due to the piezoresistive effect.

As shown in FIG. 1, the second substrate 12 has a second recess 121 formed on one surface 12a, and the second recess 121 is arranged so as to cover the thin portion 112. The pressure reference chamber 122 is formed by the space formed by the second recess 121 and the first substrate 11. The pressure reference chamber 122 is, for example, a vacuum pressure, but may be an atmospheric pressure. In this way, the sensor portion 31 is formed by the thin portion 112 of the first substrate 11 and the second recess 121 of the second substrate 12.

In the present embodiment, the sensor unit 31 is an element that detects pressure, and is formed on a protruding portion 3 of the semiconductor chip 1 as shown in FIG. When an external pressure is applied from a gas such as air or a liquid such as oil, the sensor unit 31 outputs an electric signal according to the pressure by changing the resistance value of a gauge resistance (not shown) on the thin wall portion 112. The electric signal output from the sensor unit 31 is transmitted to the pad unit 123 of the semiconductor chip 1 via a circuit wiring (not shown) formed on the one surface 11a side of the first substrate 11.

As shown in FIG. 1, the pad portion 123 is formed in a portion of the semiconductor chip 1 that becomes a supported portion 2, and is electrically connected to a circuit wiring (not shown) on the one side 11a side of the first substrate 11. The pad portion 123 is made of, for example, a metal material such as Al, and as shown in FIG. 1, a part of the inner wall and the opposite surface 12b of the through hole connecting one surface 12a of the second substrate 12 and the opposite surface 12b thereof. It is formed to cover.

The wire 4 is made of a metal material such as Au, and is connected to each of the pad portion 123 and the lead frame 5 by wire bonding as shown in FIG. 1, and these are electrically connected to each other.

The lead frame 5 is made of, for example, a metal material such as Cu, and as shown in FIG. 1, the semiconductor chip 1 is mounted on one surface thereof, and the other end on the opposite side of one end on which the semiconductor chip 1 is mounted. Is exposed from the mold resin 6.

The mold resin 6 is made of a resin material such as an epoxy resin, covers a part of the semiconductor chip 1, the wire 4, and the lead frame 5, and is formed by transfer molding or the like.

The above is the basic configuration of the semiconductor device S1.

Next, an example of the manufacturing method of the semiconductor device S1 will be described with reference to FIGS. 3A and 3B. In FIGS. 3A and 3B, similarly to FIG. 2, the sensor unit 31 is covered with a alternate long and short dash line, and an example of the irradiated portion of the laser in laser processing described later is covered with the alternate long and short dash line, which is the thinned portion 6b of the protruding portion 3. The outline of the portion and the laser low absorption material 7 are shown by broken lines.

In the manufacturing process of the semiconductor device S1, any semiconductor process can be adopted except that the laser low absorption material 7 is arranged in the protruding portion 3 of the semiconductor chip 1, and thus is related to the laser low absorption material 7. Except for the steps to be performed, a brief description will be given.

First, a semiconductor chip 1 is prepared, which is manufactured by a normal semiconductor process and in which the laser low absorption material 7 is arranged in a portion which will be a protruding portion 3 protruding from the mold resin 6 later. For example, a vacuum film forming method such as vapor deposition or sputtering is performed using a mask (not shown) so as to cover the portion of the semiconductor chip 1 where the alignment mark or serial number formed by Al is formed in the region to be the protruding portion 3. To form the laser low absorption material 7.

Next, the end portion of the semiconductor chip 1 on the portion side to be the supported portion 2 is mounted on one surface of the lead frame 5 by, for example, soldering, and then the pad portion 123 and the lead frame 5 of the semiconductor chip 1 are attached by wire bonding. Connect electrically. Then, for example, a mold (not shown) consisting of an upper mold and a lower mold is prepared, and a work in which the semiconductor chip 1, the wire 4, and the lead frame 5 are integrated is set in the mold.

Subsequently, the resin material constituting the mold resin 6 is poured into the cavity of the mold and cured to form the mold resin 6 that covers a part of the semiconductor chip 1 and the lead frame 5 and the wire 4.

When forming the mold resin 6, the resin material is prevented from flowing into at least the sensor portion 31 of the semiconductor chip 1. For example, a mold is prepared in which the region of the opposite surface of one surface 1a of the semiconductor chip 1 to be the protruding portion 3 comes into contact with the upper mold or the lower mold without a gap, or another member such as a cover (not shown) covering the sensor portion 31 is provided. It is possible to prepare it.

After forming the mold resin 6, the work is removed from the mold. As shown in FIG. 3A, the work after the formation of the mold resin 6 has a surplus of the mold resin 6 (hereinafter referred to as “surplus resin 8”) that covers the periphery of the protrusion 3 and the like when viewed from above. Is removed by laser irradiation. Specifically, light having a wavelength at which the absorption rate of the material of the mold resin 6 is high and the absorption rate of Si mainly constituting the semiconductor chip 1 is 45% or less, for example, a wavelength of 1.5 μm to 6.0 μm. Is used as a laser.

Then, the portion to which the surplus resin 8 is to be removed is irradiated with a laser having such a wavelength to remove the surplus resin 8. For example, when the region indicated by the alternate long and short dash line in FIG. 3A is irradiated with a laser, a part of the surplus resin 8 is removed as shown in FIG. 3B, and this portion becomes an exposed portion 3a. As shown by the alternate long and short dash line in FIG. 3B, this laser irradiation is repeated along the outer line of the protruding portion 3 in a top view to remove the excess resin 8, and the state shown in FIG. 2 is obtained. In this way, the semiconductor device S1 of the present embodiment can be manufactured.

Examples of the laser for removing the excess resin 8 include HoYAG (wavelength: about 1.5 μm) and ErYAG (wavelength: about 3 μm). Further, the conditions of laser irradiation, such as energy density, pulse width, and laser irradiation diameter, are set as appropriate as long as the surplus resin 8 can be removed.

Next, a preferable wavelength range of the laser and the laser low absorption material 7 will be described with reference to FIGS. 4A to 4D.

The laser used for removing the surplus resin 8 has a wavelength range in which the resin material constituting the mold resin 6 absorbs well, but the laser low absorption material 7 does not absorb much. Specifically, as for the wavelength of the laser, since the light absorption rate of a general epoxy resin system is 90% or more in the range of 0.4 μm to 11 μm as shown in FIG. 4D, the surplus resin 8 From the viewpoint of removal, it may be in the range of 0.4 μm to 11 μm. On the other hand, as shown in FIG. 4A, the absorption rate of Si, which mainly constitutes the semiconductor chip 1, is 45% or less, 0.4 μm or more and less than 1.5 μm, and more than 6 μm in the range of 1.5 μm or more and 6 μm or less. Then, it exceeds 45%. If Si constituting the semiconductor chip 1 excessively absorbs the laser in excess of 45%, damage due to heat generation may occur. Therefore, from the viewpoint of preventing this, the wavelength of the laser is in the range of 1.5 μm to 6.0 μm. It is preferable to be done.

As the laser low absorption material 7, for example, when the wavelength range of the laser is 1.5 μm to 6.0 μm, a material having a laser absorption rate of 45% or less is selected within the range. For example, _{as shown in FIG. 4B, SiO 2} has an absorption rate of 45% or less in the range of 1.5 μm to 6.0 μm, and therefore, it can be said that it is preferable to use it as the laser low absorption material 7.

On the other hand, Si ₃ N ₄ used as an insulating film has a wavelength range in which the absorptivity exceeds 45% in the range of 1.5 μm to 6.0 μm, as shown in FIG. 4C. That is, _{it can be said that Si 3} N ₄ is not preferable to be used as the laser low absorption material 7 because it absorbs a large amount of light having a predetermined wavelength among the lasers and may be damaged by heat generation.

The wavelength range of the laser for removing the excess resin 8 and the selection of the laser low absorption material 7 are performed from the above viewpoints. Although it has been explained that the laser low absorption material 7 is _{preferably Si or SiO 2} , it may be a material having an absorption rate of 45% or less in the range of 1.5 μm to 6.0 μm. , Not limited to this.

Next, the effect of the laser removal region of the semiconductor chip 1 being composed of the laser low absorption material 7 will be described. In the following description, among the components of the conventional semiconductor device, those corresponding to the components of the semiconductor device S1 of the present embodiment are designated by the same reference numerals for convenience.

In some conventional semiconductor devices, an alignment mark for alignment in a manufacturing process and a serial number of the semiconductor chip are engraved on the surface of a portion of the semiconductor chip 1 corresponding to a protruding portion 3. This serial number or the like is composed of a material used in a normal semiconductor process, for example, Al or the like, but when exposed to the atmosphere, it may peel off due to corrosion or the like and become indistinguishable. In order to prevent such a situation, the material constituting the serial number or the like is usually _{covered with a corrosion-resistant material such as Si 3} N ₄ or the like.

However, when the semiconductor chip 1 having such a configuration is irradiated with a laser for the purpose of removing the resin material or the like, the Si ₃ N ₄ covering the serial number or the like absorbs the laser and generates heat, and the serial number or the like is generated. It may be destroyed. That is, when a material having a high laser absorptance in laser processing, for example, an absorptivity of more than 45%, is arranged in the laser removal region, damage to the semiconductor chip 1 can occur.

On the other hand, since the semiconductor device S1 of the present embodiment is composed of the laser low absorption material 7 in which the laser removal region of the protrusion 3 has a laser absorption rate of 45% or less, the laser in the laser removal region It is a structure that does not cause excessive absorption. As a result, the semiconductor device S1 can suppress damage to the semiconductor chip 1 in laser processing.

According to the present embodiment, since the laser removing region of the protruding portion 3 is the semiconductor chip 1 made of the laser low absorption material 7, the semiconductor device is a semiconductor device in which damage to the semiconductor chip 1 due to laser irradiation is suppressed.

Further, a semiconductor chip 1 having a laser removal region composed of a laser low absorption material 7 is prepared, and by using this, a semiconductor device in which damage to the semiconductor chip 1 in laser processing is suppressed can be manufactured. ..

(Second Embodiment)
The semiconductor device S2 of the second embodiment will be described with reference to FIGS. 5 to 8.

In the semiconductor device S2 of the present embodiment, as shown in FIG. 5, the mold resin 6 has the resin 61 and the filler 62, and the filler 62 is arranged on the support portion 6a. Further, as shown in FIG. 6, in the semiconductor device S2, the particle size of the filler 62 contained in the support portion 6a is larger than the thickness of the thinned portion 6b in the one-side normal direction (hereinafter, simply referred to as “thickness”). .. The semiconductor device S2 differs from the first embodiment mainly in the above points. In this embodiment, these differences will be mainly described.

In the present embodiment, the mold resin 6 has a resin 61 and a filler 62, and has a support portion 6a that covers and supports a portion of the semiconductor device S2 other than the protrusion 3, and a part of the protrusion 3. It is composed of a thinning portion 6b that covers thinly. The term "thinly covered" as used herein means that the support portion 6a is covered with a thickness thinner than the thickness of the portion covering the semiconductor chip 1.

The resin 61 is an arbitrary resin material such as an epoxy resin.

The filler 62 has, for example, a spherical shape or a crushed shape, and is made of an inorganic material such as alumina or silica. The filler 62 is added for the purpose of adjusting, for example, the linear expansion coefficient and the thermal conductivity of the mold resin 6, and is distributed in the support portion 6a of the mold resin 6 as shown in FIG. As shown in FIG. 7, the filler 62 has a predetermined particle size range, for example, φ50 μm to 200 μm, but a filler 62 having a particle size larger than the thickness of the thinned portion 6b is used. As shown in FIG. 7, the filler 62 preferably has particles having a particle size smaller than the thickness of the thinned portion 6b removed. For example, when the thickness of the thinned portion 6b is 50 μm, the filler 62 preferably has particles having a particle size of 50 μm or less removed by filtration or the like. The reason for this will be described later in the description of the manufacturing method of the semiconductor device S2.

The thinned portion 6b is mainly composed of the resin 61. As shown in FIG. 6, the thinning portion 6b has a relationship of t1 <t2 when the thickness in the one-sided normal direction is t1 and the particle size of the filler 62 is t2. That is, the thickness of the thinned portion 6b is smaller than the particle size of the filler 62.

Next, an example of the manufacturing method of the semiconductor device S2 will be described with reference to FIG. 8, except that the mold resin 6 is configured to include the resin 61 and the filler 62 and the filler 62 is arranged on the support portion 6a. Is the same as that of the first embodiment. Therefore, here, the step of forming the mold resin 6 containing the filler 62 will be mainly described.

A work in which the semiconductor chip 1, the wire 4, and the lead frame 5 are integrated is produced, and as shown in FIG. 8, a mold 200 for setting the work is prepared. Specifically, for example, as shown in FIG. 8, the upper die 201 and the lower die 202 form a first cavity 203 and a thinned portion 6b on which the support portion 6a of the mold resin 6 is formed. A mold 200 having a second cavity 204 is prepared.

Next, the resin material constituting the resin 61 and the filler 62 are prepared. At this time, a filler 62 having a particle size larger than the gap between the protruding portion 3 and the upper die 201 in the one-side normal direction of the one surface 1a of the semiconductor chip 1 is prepared. Then, as shown in FIG. 8, the material of the mold resin 6 is injected into the first cavity 203 from an injection port (not shown) and cured to form the mold resin 6.

At the time of forming the mold resin 6, the material of the mold resin 6 flows from the first cavity 203 side to the second cavity 204 side. At this time, since the particle size of the filler 62 is larger than the gap between the boundary between the first cavity 203 and the second cavity 204 of the upper mold 201 and the semiconductor chip 1, the second cavity is larger than the gap. It cannot enter the space on the 204 side. As a result, the filler 62 is arranged in the support portion 6a of the formed mold resin 6, but is not arranged in the thinning portion 6b. In other words, while using a material containing the resin 61 and the filler 62, a mold resin 6 having a partially filler-less region, that is, a thinned portion 6b is formed.

The term "fillerless" as used herein is unavoidable due to factors such as not only a state in which the filler 62 is not mixed at all, but also factors such as difficulty in removing the filler 62 by filtration or the like, or a part of the filler 62 being chipped. It means that a state in which a filler having a fine particle size is present is also included.

Here, in the conventional manufacturing method in which the filler-less resin is separately used, a film made of the filler-less resin is formed on a part of the protruding portion 3 by, for example, a dispenser coating, then the mold resin 6 is formed, and the filler-less resin is laser-processed. It is to be removed. However, if the film made of the fillerless resin is formed thick, it is difficult for the laser during laser processing to reach the portion of the fillerless resin located on the protruding portion 3 side, that is, the portion deep as seen from the surface of the fillerless resin. There is concern that it will become. Further, the temporary formation of the film made of the filler-less resin causes dimensional restrictions in the subsequent step of forming the mold resin 6.

On the other hand, in the case of the method for manufacturing the semiconductor device of the present embodiment, the portion containing the filler 62 and the fillerless portion are collectively formed in the forming step of the mold resin 6, so that the above problem occurs. There is no.

According to the present embodiment, the effect of the first embodiment can be obtained, and the thinned portion 6b that is selectively filler-less among the mold resin 6 containing the filler 62 is provided, and the filler-less resin is separately used. It is a semiconductor device with a configuration that can be manufactured without any problems.

Further, by making the gap between the protruding portion 3 of the semiconductor chip 1 and the mold 200 smaller than the particle size of the filler 62 contained in the mold resin 6, the support portion 6a containing the filler 62 and the filler It is possible to collectively form the thinned portion 6b that has been made less. That is, since the fillerless thinned portion 6b can be selectively formed without using a fillerless resin separately, it is possible to manufacture a semiconductor device in which the laser removal region or its vicinity is fillerless more easily than in the past. ..

(Other embodiments)
The semiconductor device and the manufacturing method thereof shown in each of the above-described embodiments show an example of the present invention, and are not limited to each of the above-described embodiments, but are described in the scope of claims. It can be changed as appropriate within.

(1) In the first embodiment, the case where the thinned portion 6b is made of the same resin material as the mold resin 6 has been described. However, for the purpose of relaxing the molding pressure of the molding resin 6 on the semiconductor chip 1 and reducing the residual stress of the semiconductor chip 1, a thin film made of a low elasticity material covering the portion to be the protruding portion 3 of the semiconductor chip 1 is formed in advance. The semiconductor chip 1 that has been used may be used. Examples of this low elasticity material include polyacrylic, silicone resin, and polyimide. In this case, for example, as shown in FIG. 9, it is conceivable to form the mold resin 6 by using the semiconductor chip 1 on which the low elasticity thin film 9 made of the low elasticity material is formed.

Here, as a conventional method for manufacturing a semiconductor device, as shown in FIG. 10, specifically, as shown in FIG. 9, a mold 400 and a film 500 made of an upper mold 401 and a lower mold 402 are prepared. .. The mold 400 includes a third cavity 403 that forms a support portion 6a of the mold resin 6, and a fourth cavity 404 for setting a portion of the semiconductor chip 1 that becomes a protruding portion 3. As shown in FIG. 10, the film 500 is arranged along the inner wall of the upper die 401. Then, the semiconductor chip 1 is set in the mold 400 so that the mold matching pressure is applied to the portion of the semiconductor chip 1 exposed from the mold resin 6 via the film 500. As a result, the pressure of the mold matching of the mold 400 is alleviated from being transmitted to the semiconductor chip 1 through the film 500, and the residual stress of the semiconductor chip 1 can be reduced. However, this method requires a film 500 in addition to the mold 400.

Therefore, as shown in FIG. 9, when the semiconductor chip 1 is set in the mold 300 composed of the upper mold 301 and the lower mold 302 and the molds are matched, the portion of the semiconductor chip 1 that comes into pressure contact with, for example, the upper mold 301. The low elasticity thin film 9 is formed. As a result, the pressure due to the contact between the semiconductor chip 1 and the upper die 301 is relieved by passing through the low elasticity thin film 9. Therefore, even if the film 500 is not used, the residual stress caused by excessive application of the mold matching pressure of the mold 300 to the semiconductor chip 1 can be reduced, and the deterioration of the reliability of the semiconductor chip 1 due to this can be suppressed. It is possible to manufacture a highly effective semiconductor device.

A part or all of the low elasticity thin film 9 may be removed by laser processing, or may be left if the thickness has a small influence on the operation of the sensor unit 31, for example, 150 μm or less.

(2) In each of the above embodiments, an example having a cantilever structure in which one end of the semiconductor chip 1 is supported by the mold resin 6 and the other end is a free end has been described. However, the semiconductor chip 1 may not necessarily have a cantilever structure, as long as the laser removal region is composed of the laser low absorption material 7 or is separately arranged. Specifically, the semiconductor chip 1 has a structure in which one end and the other end thereof are covered with different mold resins 6 and supported, and the region between the mold resins 6 protrudes from the mold resin 6, that is, It may have a double-sided structure.

In this case, the portion of the semiconductor chip 1 covered with the mold resin 6 becomes the supported portion 2, and the remaining portion, that is, the portion protruding from the mold resin 6 corresponds to the protruding portion 3.

(3) In each of the above embodiments, as shown in FIG. 2, a portion of one surface 1a of the semiconductor chip 1 located on the back side of the sensor portion 31 (hereinafter referred to as “sensor back side portion”) is exposed from the mold resin 6. The example of the part 3a has been described. However, the back side portion of the sensor may be the covering portion 3b. At this time, the thickness of the thinned portion 6b in the one-sided normal direction is preferably set to a degree that does not affect the operation of the sensor portion 31, for example, 150 μm or less. On the contrary, all the protruding portions 3 may be exposed from the mold resin 6.

(4) In each of the above embodiments, an example in which a part of the mold resin 6, that is, the surplus resin 8 is removed by laser irradiation has been described, but the present invention is not limited to this, and even if the mold resin 6 is removed by another treatment such as a chemical treatment. good. In this case, instead of the laser low absorption material 7, a material durable to the chemical solution used for the chemical solution treatment may be used. That is, in the semiconductor chip 1, the region that becomes a part of the exposed portion 3a by removing a part of the mold resin 6 from the protruding portion 3, that is, the mold resin removing region is one of the mold resin 6 such as laser processing. It suffices if a durable material is arranged for the removing means of the portion. Specifically, the durable material is the laser low absorption material 7 when the removing means is laser processing, and is insoluble in the chemical solution used when the removing means is chemical treatment. Alternatively, it is a poorly soluble chemical durable material. In the case of chemical treatment, the mold resin removal area may be covered with the chemical durable material or made of the chemical durable material.

(5) In the second embodiment, an example in which the laser removal region of the semiconductor chip 1 is composed of the laser low absorption material 7 and the mold resin 6 containing the filler 62 is partially filler-less has been described. .. However, when the filler-less portion is left without laser processing, the semiconductor chip 1 may be configured by using a semiconductor chip that is not intentionally composed of a part thereof by the laser low absorption material 7. .. Even with such a configuration, the mold resin 6 is configured to include the filler 62, and the support portion 6a containing the filler 62 and the fillerless thinned portion 6b are collectively formed at the time of molding the mold resin 6. Since it is formed, it can be manufactured more easily than in the past.

(6) In each of the above embodiments, an example in which the semiconductor chip 1 is used as a pressure sensor has been described, but the present invention is not limited to this, and the semiconductor chip 1 may be, for example, a magnetic sensor, an optical sensor, or another semiconductor sensor. ..

1 Semiconductor chip 2 Supported part 3 Protruding part 3a Exposed part 3b Covered part 6 Molded resin 6a Supporting part 6b Thinning part 62 Filler 7 Laser low absorption material

Claims (9)

A semiconductor chip (1) having a sensor unit (31) that outputs a signal according to a physical quantity, and
A semiconductor device including a mold resin (6) that covers a part of the semiconductor chip.
The portion of the semiconductor chip that protrudes from the mold resin is used as the protruding portion (3), and the exposed portion (3a) that is exposed from the mold resin is the portion of the mold resin that covers the protruding portion. A part thereof is irradiated with a laser to be removed, so that the laser removal region exposed from the mold resin is included.
The laser removal region is a semiconductor device that is a region composed of a laser low absorption material (7) having a laser absorption rate of 45% or less within a wavelength range of 1.5 μm or more and 6.0 μm or less. A semiconductor chip (1) having a sensor unit (31) that outputs a signal according to a physical quantity, and
A semiconductor device including a mold resin (6) that covers a part of the semiconductor chip.
The portion of the semiconductor chip that protrudes from the mold resin is used as the protruding portion (3), and the exposed portion (3a) that is exposed from the mold resin is the portion of the mold resin that covers the protruding portion. A part thereof is irradiated with a laser to be removed, so that the laser removal region exposed from the mold resin is included.
The laser removal region is a semiconductor device that is a region covered with a laser low absorption material (7) having a laser absorption rate of 45% or less within a wavelength range of 1.5 μm or more and 6.0 μm or less. The semiconductor device according to claim 1 or 2, wherein the laser low absorption material is _{any one of Si, SiO 2} , SiC, sapphire, GaN, GaAs, and InP. The protruding portion has a coating portion (3b) at least partially covered with the mold resin.
The mold resin contains a filler (62) and contains a filler (62).
The normal direction of the semiconductor chip with respect to one surface on which the coating portion is formed is defined as the one-side normal direction, and the portion of the mold resin that covers the coating portion is defined as a thinning portion (6b).
The filler according to any one of claims 1 to 3, wherein the filler has a particle size larger than the thickness of the thinned portion in the one-sided normal direction and is arranged in a portion different from the thinned portion. Semiconductor device. A semiconductor chip (1) having a sensor unit (31) that outputs a signal according to a physical quantity, and
A semiconductor device including a mold resin (6) that covers a part of the semiconductor chip.
A portion of the semiconductor chip that protrudes from the mold resin is used as a protrusion (3), and the protrusion has a coating portion (3b) that is at least partially covered with the mold resin.
The mold resin contains a filler (62) and contains a filler (62).
The normal direction of the semiconductor chip with respect to one surface on which the coating portion is formed is defined as the one-side normal direction, and the portion of the mold resin that covers the coating portion is defined as a thinning portion (6b).
The filler is a semiconductor device having a particle size larger than the thickness of the thinned portion in the one-sided normal direction and arranged in a portion different from the thinned portion. Preparing a semiconductor chip (1) having a sensor unit (31) that outputs a signal according to a physical quantity, and
To prepare a mold (200) used to form a mold resin (6) that covers at least a part of the semiconductor chip, and to prepare a mold (200).
The semiconductor chip is set in the mold, and the resin material constituting the mold resin is poured and cured to form the mold resin.
After forming the mold resin, a part of the semiconductor chip protruding from the mold resin (3) is irradiated with a laser to expose the part from the mold resin (3a). Including, forming
In preparing the semiconductor chip, the laser low absorption material (7) having a laser absorption rate of 45% or less is arranged in a portion of the mold resin covered by a portion of the mold resin that is irradiated and removed by the laser. A method for manufacturing a semiconductor device for preparing the semiconductor chip. The method for manufacturing a semiconductor device according to claim 6, wherein in forming the exposed portion, a laser having a wavelength in the range of 1.5 μm or more and 6.0 μm or less is used as the laser. In forming the mold resin, the resin material containing the filler (62) is used.
In preparing the mold, it is requested to prepare the mold in which the gap between the mold and the portion of the semiconductor chip that becomes the protruding portion after the formation of the mold resin is smaller than the particle size of the filler. Item 6. The method for manufacturing a semiconductor device according to Item 6. Preparing a semiconductor chip (1) having a sensor unit (31) that outputs a signal according to a physical quantity, and
To prepare a mold (200) used to form a mold resin (6) that covers at least a part of the semiconductor chip, and to prepare a mold (200).
Including that the semiconductor chip is set in the mold, the resin material constituting the mold resin is poured and cured, and the mold resin is formed.
In forming the mold resin, the resin material containing the filler (62) is used.
In preparing the mold by using the portion of the semiconductor chip that protrudes from the mold resin after the formation of the mold resin as the projecting portion (3), it becomes the projecting portion of the mold and the semiconductor chip. A method for manufacturing a semiconductor device in which the mold having a gap between the portions is smaller than the particle size of the filler is prepared.

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