Search

CN-122028526-A - Single photon avalanche diode device and manufacturing method thereof

CN122028526ACN 122028526 ACN122028526 ACN 122028526ACN-122028526-A

Abstract

Embodiments of the present disclosure provide a single photon avalanche diode and a method of manufacturing the same. The single photon avalanche diode device comprises a photosensitive absorption layer and a light path layer which are sequentially stacked, wherein the light path layer is arranged on the light inlet side of the photosensitive absorption layer, the light path layer is used for transmitting incident light, the light path layer has a transmittance to photons of a target wave band in the incident light which is larger than that to photons of a non-target wave band, the photosensitive absorption layer comprises a depletion avalanche layer which is used for absorbing photons of the target wave band and generating avalanche current, and the depletion avalanche layer is arranged adjacent to the light path layer. The dark noise level can be reduced, the low working voltage of the single photon avalanche diode device can be realized, and the application difficulty of the single photon avalanche diode device is reduced.

Inventors

  • XU QING

Assignees

  • 武汉北极芯微电子有限公司

Dates

Publication Date
20260512
Application Date
20260130

Claims (10)

  1. 1. The single photon avalanche diode device is characterized by comprising a photosensitive absorption layer and an optical path layer which are sequentially stacked, wherein the optical path layer is arranged on the light inlet side of the photosensitive absorption layer; The light path layer is used for transmitting incident light, and the transmittance of the light path layer to photons of a target wave band in the incident light is larger than the transmittance to photons of a non-target wave band; the photosensitive absorption layer comprises a depletion avalanche layer, wherein the depletion avalanche layer is used for absorbing photons of a target wave band and generating avalanche current; Wherein the depletion avalanche layer is disposed adjacent to the optical path layer.
  2. 2. The single photon avalanche diode device according to claim 1, wherein the depletion avalanche layer comprises a PN junction region and an absorption avalanche region; The absorption avalanche region is used for absorbing photons of a target wave band, inducing an avalanche effect and generating avalanche current; wherein the absorption avalanche region is located at one side of the PN junction region, and the absorption avalanche region at least partially overlaps with the PN junction region.
  3. 3. The single photon avalanche diode device according to claim 2, wherein a width of the absorption avalanche region in a first direction is greater than a width of the PN junction region in the first direction; The first direction is a stacking direction of the light path layer and the photosensitive absorption layer.
  4. 4. The single photon avalanche diode device according to claim 1, wherein the optical path layer comprises an antireflection layer, a filter layer, and a lens layer stacked in this order along a first direction, the lens layer being located on a surface of the optical path layer on a side away from the photosensitive absorption layer, the antireflection layer being located on a surface of the optical path layer on a side close to the photosensitive absorption layer; The lens layer is used for converging incident light to the filter layer; the filter layer is used for screening out light rays of non-target wave bands in incident light; the anti-reflection layer is used for weakening the reflection of light rays at interfaces of different layers.
  5. 5. The single photon avalanche diode device according to claim 4, wherein the optical path layer further comprises a second isolation trench surrounding the filter layer and the anti-reflection layer, a central axis of the second isolation trench being parallel to the first direction.
  6. 6. The single photon avalanche diode device according to claim 1, wherein the photoactive absorption layer further comprises a total reflection layer, the total reflection layer being located on a side of the depletion avalanche layer remote from the optical path layer.
  7. 7. The single photon avalanche diode device according to claim 5, wherein the optical path layer further comprises a micro-reflective structure on a side of the anti-reflective layer adjacent to the photosensitive absorption layer; the micro-reflection structure is used for reflecting photons reflected by the total reflection layer back into the depletion avalanche layer.
  8. 8. The single photon avalanche diode device according to claim 5, wherein the photosensitive absorber layer further comprises a first isolation trench surrounding a perimeter of the depletion avalanche layer, a central axis of the first isolation trench being parallel to a first direction.
  9. 9. The single photon avalanche diode device according to claim 8, wherein the first end surface of the first isolation trench extends to a surface of the photosensitive absorption layer on a side close to the light path layer, the first end surface of the second isolation trench extends to a surface of the light path layer on a side close to the photosensitive absorption layer, and the first end surface of the first isolation trench is disposed in contact with the first end surface of the second isolation trench.
  10. 10. A method of manufacturing a single photon avalanche diode device, the method comprising: Providing a semiconductor substrate, and forming an epitaxial layer on the semiconductor substrate; Forming a photosensitive absorber layer in the epitaxial layer, the photosensitive absorber layer comprising a depletion avalanche layer; And forming an optical path layer on the photosensitive absorption layer, wherein the optical path layer is arranged adjacent to the depletion avalanche layer, and the transmittance of the optical path layer to photons of a target wave band is larger than that of photons of a non-target wave band.

Description

Single photon avalanche diode device and manufacturing method thereof Technical Field The present disclosure relates to the field of semiconductor technology, and in particular, to a single photon avalanche diode device and a method of manufacturing the same. Background A Single-photon avalanche diode device (SPAD) is a Single-photon detector manufactured by using a semiconductor manufacturing process, and has the advantages of excellent Single-photon response and resolution, small volume, easy integration, low working voltage, no interference of magnetic field, good reliability, low cost and the like, so that the Single-photon avalanche diode device is greatly focused in recent years and rapidly becomes the first choice of a photoelectric detector in a low-flux photon detection technology. The traditional silicon-based SPAD is of a surface shallow junction structure, the multiplication region is shallow, the thickness is thin, the response rate to green light and blue light is high, and the response rate to near infrared photons is low. But green light and blue light belong to visible light, and are greatly harmful to human eyes. The visible light is easy to be interfered by the change of the ambient light, so that the detection efficiency of the conventional SPAD on the visible light is drastically reduced, and the requirement of the integral detector cannot be met. The near infrared light source has the advantages of relatively small influence of the change of the ambient light, small damage to human eyes and the like, so that the near infrared light source becomes the optimal light source selection for high-precision and high-stability detection. However, the detection efficiency of the conventional SPAD on the near infrared photons is very low, and the application requirement of high detection efficiency cannot be met. In the prior art, in order to improve the detection efficiency of the SPAD on the infrared photons, the SPAD is set to be a deep PN junction structure or the depth of a depletion region is increased, but the high dark noise level is caused, the breakdown voltage of the SPAD is higher, the SPAD needs larger working voltage, but the high-voltage boosting is difficult to realize, and the cost is high. Therefore, a SPAD that can combine high infrared photon detection efficiency, low dark noise level, and low operating voltage is needed. Disclosure of Invention Embodiments of the present disclosure provide a single photon avalanche diode device and a method of manufacturing the same. In a first aspect, an embodiment of the present disclosure provides a single photon avalanche diode device, including a photosensitive absorption layer and an optical path layer stacked in sequence, where the optical path layer is disposed on a light inlet side of the photosensitive absorption layer; The light path layer is used for transmitting incident light, and the transmittance of the light path layer to photons of a target wave band in the incident light is larger than the transmittance to photons of a non-target wave band; the photosensitive absorption layer comprises a depletion avalanche layer, wherein the depletion avalanche layer is used for absorbing photons of a target wave band and generating avalanche current; Wherein the depletion avalanche layer is disposed adjacent to the optical path layer. In some embodiments, the depletion avalanche layer includes a PN junction region and an absorption avalanche region; The absorption avalanche region is used for absorbing photons of a target wave band, inducing an avalanche effect and generating avalanche current; wherein the absorption avalanche region is located at one side of the PN junction region, and the absorption avalanche region at least partially overlaps with the PN junction region. In some embodiments, a width of the absorbing avalanche region in the first direction is greater than a width of the PN junction region in the first direction; The first direction is a stacking direction of the light path layer and the photosensitive absorption layer. In some embodiments, the optical path layer includes an antireflection layer, a filter layer, and a lens layer stacked in order along a first direction, the lens layer being located on a surface of a side of the optical path layer away from the photosensitive absorption layer, the antireflection layer being located on a surface of a side of the optical path layer close to the photosensitive absorption layer; The lens layer is used for converging incident light to the filter layer; the filter layer is used for screening out light rays of non-target wave bands in incident light; the anti-reflection layer is used for weakening the reflection of light rays at interfaces of different layers. In some embodiments, the optical path layer further includes a second isolation groove surrounding the filter layer and the anti-reflection layer, a central axis of the second isolation groove being parallel to the first d