US-12627115-B2 - Semiconductor laser drive device, electronic equipment, and method for manufacturing semiconductor laser drive device

US12627115B2US 12627115 B2US12627115 B2US 12627115B2US-12627115-B2

Abstract

In a semiconductor laser drive device, wiring inductance between a semiconductor laser and a laser driver is reduced. A substrate has a laser driver built inside. A semiconductor laser is mounted on one surface of a substrate of the semiconductor laser drive device and emits irradiation light from an irradiation surface. A connection wiring electrically connects the laser driver and the semiconductor laser with a wiring inductance of 0.5 nH or less. A passive component is disposed to face a side of the semiconductor laser having the least number of pads and connects to the semiconductor laser and the laser driver.

Inventors

Nobuaki Kaji
Tatsuya Oiwa
Hirohisa Yasukawa

Assignees

SONY SEMICONDUCTOR SOLUTIONS CORPORATION

Dates

Publication Date: 20260512
Application Date: 20200721
Priority Date: 20190925

Claims (20)

1 . A semiconductor laser drive device, comprising: a substrate with a laser driver built inside; a semiconductor laser mounted on one surface of the substrate; connection wiring that electrically connects the laser driver and the semiconductor laser, wherein the connection wiring has a wiring inductance of 0.5 nH or less; and a passive component that is disposed to face a side of the semiconductor laser having a least number of pads and connects to the semiconductor laser and the laser driver, wherein the passive component is provided on a same plane as the semiconductor laser in a cross-sectional view, and wherein at least a part of the passive component is disposed to overlap above the laser driver.
2 . The semiconductor laser drive device according to claim 1 , wherein the passive component forms a part of a path through which the laser driver drives the semiconductor laser.
3 . The semiconductor laser drive device according to claim 1 , wherein the passive component includes a capacitor.
4 . The semiconductor laser drive device according to claim 3 , wherein the capacitor is a decoupling capacitor that connects a power supply potential and a ground potential of the laser driver.
5 . The semiconductor laser drive device according to claim 1 , further comprising: a photodiode that is disposed to face the side of the semiconductor laser having the least number of pads and monitors light intensity of laser light emitted from the semiconductor laser, wherein the laser driver drives the semiconductor laser on a basis of the light intensity monitored by the photodiode.
6 . The semiconductor laser drive device according to claim 1 , wherein the connection wiring has a length of 0.5 mm or less.
7 . The semiconductor laser drive device according to claim 1 , wherein the connection wiring is through a connecting via provided on the substrate.
8 . The semiconductor laser drive device according to claim 1 , wherein a part of the semiconductor laser is disposed to overlap above the laser driver.
9 . The semiconductor laser drive device according to claim 8 , wherein a portion of 50% or less of an area of the semiconductor laser is disposed to overlap above the laser driver.
10 . A method for manufacturing a semiconductor laser drive device, comprising: forming a laser driver on an upper surface of a support plate; forming connection wiring of the laser driver and forming a substrate with the laser driver built inside; mounting a semiconductor laser on one surface of the substrate and forming connection wiring that electrically connects, via the connection wiring, the laser driver and the semiconductor laser, wherein the connection wiring has with a wiring inductance of 0.5 nH or less; and disposing a passive component connecting the semiconductor laser and the laser driver to face a side of the semiconductor laser having a least number of pads, wherein the passive component is provided on a same plane as the semiconductor laser in a cross-sectional view, and wherein at least a part of the passive component is disposed to overlap above the laser driver.
11 . Electronic equipment, comprising: an optical system; semiconductor laser drive device that receives light from the optical system, the semiconductor laser device including: a substrate with a laser driver built inside; a semiconductor laser mounted on one surface of the substrate; connection wiring that electrically connects the laser driver and the semiconductor laser, wherein the connection wiring has with a wiring inductance of 0.5 nH or less; and a passive component that is disposed to face a side of the semiconductor laser having a least number of pads and connects to the semiconductor laser and the laser driver, wherein the passive component is provided on a same plane as the semiconductor laser in a cross-sectional view; and a controller that processes signals from the semiconductor laser drive device.
12 . The electronic equipment according to claim 11 , wherein the passive component forms a part of a path through which the laser driver drives the semiconductor laser.
13 . The electronic equipment according to claim 11 , wherein at least a part of the passive component is disposed to overlap above the laser driver.
14 . The electronic equipment according to claim 11 , wherein the passive component includes a capacitor.
15 . The electronic equipment according to claim 14 , wherein the capacitor is a decoupling capacitor that connects a power supply potential and a ground potential of the laser driver.
16 . The electronic equipment according to claim 11 , further comprising: a photodiode that is disposed to face the side of the semiconductor laser having the least number of pads and monitors light intensity of laser light emitted from the semiconductor laser, wherein the laser driver drives the semiconductor laser on a basis of the light intensity monitored by the photodiode.
17 . The electronic equipment according to claim 11 , wherein the connection wiring has a length of 0.5 mm or less.
18 . The electronic equipment according to claim 11 , wherein a part of the semiconductor laser is disposed to overlap above the laser driver.
19 . The electronic equipment according to claim 18 , wherein a portion of 50% or less of an area of the semiconductor laser is disposed to overlap above the laser driver.
20 . The method for manufacturing a semiconductor laser drive device according to claim 10 , wherein the passive component includes a capacitor.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application is a national stage application under 35 U.S.C. 371 and claims the benefit of PCT Application No. PCT/JP2020/028243, having an international filing date of 21 Jul. 2020, which designated the United States, which PCT application claimed the benefit of Japanese Priority Patent Application JP 2019-174518 filed 25 Sep. 2019, the entire disclosures of each contents of which are incorporated herein by reference. TECHNICAL FIELD The present technology relates to a semiconductor laser drive device. More specifically, the present technology relates to a semiconductor laser drive device including a substrate with a laser driver built inside and a semiconductor laser, electronic equipment, and a method for manufacturing a semiconductor laser drive device. BACKGROUND ART Conventionally, in an electronic device having a distance measuring function, a distance measuring method called time of flight (ToF) has often been used. This ToF is a method in which a light-emitting part irradiates an object with sine-wave or rectangular-wave irradiation light, a light-receiving part receives reflected light from the object, and a distance measuring operation part measures a distance from a phase difference between the irradiation light and the reflected light. There is known an optical module in which a light-emitting element and an electronic semiconductor chip for driving the light-emitting element are housed in a casing and integrated in order to realize the distance measuring function as described above. For example, there has been proposed an optical module including: a laser diode array arrayed and mounted on an electrode pattern of a substrate; and a driver integrated circuit (IC) electrically connected to the laser diode array (e.g., see Patent Literature 1). CITATION LIST Patent Literature PTL 1: JP 2009-170675A SUMMARY Technical Problem In the related art described above, the laser diode array and the driver IC are integrated and configured as an optical module. However, in this related art, the laser diode array and the driver IC are electrically connected by a plurality of wires, and wiring inductance therebetween increases, whereby there is a possibility that the driving waveform of the semiconductor laser may be distorted. This is particularly problematic for ToF driven at hundreds of megahertz. The present technology has been developed in view of such a situation, and it is desirable to reduce wiring inductance between a semiconductor laser and a laser driver in a semiconductor laser drive device. Solution to Problem According to an embodiment of the present technology, there are provided a semiconductor laser drive device and electronic equipment provided with the semiconductor laser drive device, the device including: a substrate with a laser driver built inside; a semiconductor laser mounted on one surface of the substrate; connection wiring that electrically connects the laser driver and the semiconductor laser with a wiring inductance of 0.5 nH or less; and a passive component that is disposed to face a side of the semiconductor laser having the least number of pads and connects to the semiconductor laser and the laser driver. Therefore, the laser driver and the semiconductor laser are electrically connected with a wiring inductance of 0.5 nH or less, and the passive component is disposed to face the side of the semiconductor laser having the least number of pads, thereby having an effect of shortening the wiring length. Further, in the embodiment the passive component may form a part of a path through which the laser driver drives the semiconductor laser. This brings an effect of shortening the wiring length of the path through which the laser driver drives the semiconductor laser. Further, in the first embodiment, at least a part of the passive component may be disposed to overlap above the laser driver. This brings an effect of shortening the wiring length between the passive component and the laser driver. Further, in the embodiment, the passive component may include a capacitor. In this case, the capacitor may be a decoupling capacitor that connects a power supply potential and a ground potential of the laser driver. This brings an effect of reducing high-frequency noise. Moreover, in the embodiment, the semiconductor laser drive device further includes a photodiode that is disposed to face the side of the semiconductor laser having the least number of pads and monitors light intensity of laser light emitted from the semiconductor laser, in which the laser driver may drive the semiconductor laser on the basis of the light intensity monitored by the photodiode. This brings an effect of ensuring the amount of light incident on the photodiode and improving the incidence sensitivity. Further, in the embodiment, the connection wiring desirably has a length of 0.5 mm or less. Further, the connection wiring is more preferably 0.3 mm or less. Further, in the