Refractive index engineering for brightness enhancement and kink suppression in light-emitting devices

Abstract

A system and method are provided for refractive index engineering for brightness enhancement and kink suppression in light emitter devices. An exemplary light-emitter device may include a first region including a first semiconductor material, an active region disposed on the first region and including a pump active region between a front end and a back end of the light-emitter device, and a plurality of loss structures disposed along at least a portion of at least one side of the pump active region. The plurality of loss structures may be disposed between the front end and the back end of the light-emitter device. The plurality of loss structures may include two or more continuous etched lines. The plurality of loss structures may include two or more discontinuous etched features.

Description

[Technical Field]

[0001] Aspects of the present disclosure relate to optical communication-based solutions. More particularly, certain implementations of the present disclosure relate to methods and systems for implementing and utilizing refractive index engineering for brightness enhancement and kink suppression in light emitter devices. [Background technology]

[0002]

[0002] The limitations and disadvantages of conventional solutions for implementing and using optical emitter devices, particularly edge-emitting devices, will become apparent to those skilled in the art through a comparison of such systems with certain aspects of the present disclosure set forth in the remainder of this application, including by reference to the drawings. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent Application Serial No. 17 / 249,916 Summary of the Invention

[0004]

[0003] As more fully set forth in the claims, a system and method for refractive index engineering for the purpose of improving brightness and suppressing kinks in an optical emitter device is provided, substantially as shown in and / or substantially described in connection with at least one of the drawings.

[0005] These and other advantages, aspects and novel features of the present disclosure, as well as details of illustrated embodiments thereof, will be more fully understood from the following description and drawings. [Brief explanation of the drawings]

[0006] [Figure 1]

[0005] FIG. 1 illustrates an exemplary light emitter device including a non-absorbing mirror (NAM) and a process for fabricating the same. [Figure 2]

[0006] FIG. 1 is a top view illustrating an exemplary light emitter device including a non-absorbing mirror (NAM) and showing various details thereof. [Figure 3]

[0007] 1 illustrates an exemplary light emitter device including a non-absorbing mirror (NAM) and a loss structure. [Figure 4]

[0008] 1A-1C illustrate different exemplary loss structures that may be used in a light emitter device that includes a non-absorbing mirror (NAM). [Figure 5A]

[0009] 10 is a graph illustrating optical power performance of an exemplary optical emitter device without emitter-side refractive index engineering. [Figure 5B] 10 is a graph illustrating optical power performance of an exemplary optical emitter device without emitter-side refractive index engineering. [Figure 6A]

[0010] 10 is a graph illustrating optical power performance of an exemplary optical emitter device having patterned refractive index variations on the emitter side. [Figure 6B] 10 is a graph illustrating optical power performance of an exemplary optical emitter device having patterned refractive index variations on the emitter side. [Figure 7]

[0011] 10 is a graph showing the improvement in slow axis performance when using a lossy structure. [Figure 8]

[0012] 10 is a graph showing the improvement in luminance performance when using a lossy structure. DETAILED DESCRIPTION OF THE INVENTION

[0007]

[0013] The present disclosure is directed to optical emitter devices (e.g., laser emitters) and solutions for improving their operation and / or performance. In particular, embodiments according to the present disclosure are directed to and / or incorporate the use of refractive index (RI) engineering for brightness enhancement and kink suppression in optical emitter devices, particularly edge-emitting lasers.

[0008]

[0014] In this regard, certain optical emitter devices may have certain shortcomings or problems, particularly with respect to aspects such as brightness and / or power kinks. For example, wide multimode edge-emitting lasers may need to operate and / or provide higher levels of power to enable use in certain applications, such as industrial and lidar applications. This may be done, for example, by increasing the emitter width. However, increasing the emitter width may cause problems and / or pose challenges. For example, increasing the emitter width may reduce the laser's brightness and may also result in a kink (discontinuity) in the optical power. In this regard, brightness is an important performance characteristic of lasers, representing the amount of optical power emitted over a specific angle. The brighter the laser, the greater the percentage of the total emitted power that can be easily collected by the module optics. Therefore, reduced brightness is undesirable. Similarly, the presence of a power kink is undesirable. In this regard, the presence of a kink in the laser's output power may render the laser virtually useless for operation, as the delivered power may be unstable over time. Furthermore, discontinuities in optical power pose a reliability risk to the device, and it is therefore desirable to have a solution that addresses these issues, and to do so without compromising or otherwise affecting the performance of the optical emitter device.

[0009]

[0015] However, conventional solutions, if any, may have shortcomings and / or limitations to address these issues. For example, solutions targeted at kink suppression do not address brightness and may introduce further issues, such as far-field instability, high far-field divergence at low currents, and / or burn-in (BI) failures, and / or may have disadvantages in terms of cost and yield, particularly solutions with reduced fill factor resulting in fewer chips per wafer.

[0010]

[0016] Regarding solutions aimed at improving brightness, one approach may be the use of increased emitter length. However, such an approach may have disadvantages in terms of cost and yield, especially since increasing emitter length results in a reduction in the number of chips per wafer. Other approaches may include the use of lateral trenches for index guiding and / or the use of phase structures added to the front and rear facets. However, such approaches may not address issues related to kink suppression.

[0011]

[0017] It would therefore be desirable and preferred to have a solution that addresses both issues (brightness enhancement and kink suppression) while also eliminating and / or otherwise mitigating the disadvantages of any conventional solutions.

[0012]

[0018] The proposed solution based on the present disclosure is directed to solving both the brightness degradation and the appearance of power kinks, and to doing so in an improved manner, e.g., without reducing the fill factor, or conversely, while maintaining adequate brightness and kink-free behavior even for high fill factor designs. According to the present disclosure, light-emitter devices may be designed and / or modified to allow refractive index engineering on the light-emitting portion (e.g., laser emitter) side to introduce losses for higher-order modes that are responsible for the presence of kinks in the device's light-current (LI) curve and adversely affect brightness. In this regard, several techniques may be used to bring about the necessary refractive index changes, such as by configuring or modifying the etching of the active region or by selective removal of quantum wells (QWs) together with overgrowths (e.g., when using non-absorbing mirror (NAM) techniques, which may also be used for the front and rear facets).

[0013]

[0019] In various exemplary embodiments consistent with the present disclosure, a light emitter device can incorporate a structure (hereinafter referred to as a "loss structure") configured to provide sufficient loss to achieve both kink suppression and brightness enhancement. Such a loss structure may be configured (e.g., by setting or modifying various properties and / or aspects thereof) to achieve the desired improvements in terms of enhanced brightness and kink suppression, and to do so in a manner that does not increase cost, decrease yield, or detract from the overall performance of the light emitter device. Such exemplary embodiments and features thereof are described in more detail below with reference to FIGS. 1-8.

[0014]

[0020] 1 illustrates an exemplary light emitter device including a non-absorbing mirror (NAM) and a process for fabricating the same. Illustrated in FIG. 1 is a light emitter device 100 and a process flow 110.

[0015]

[0021] The light-emitter device 100 may be a quantum well (QW)-based edge-emitting laser device, which may be in the form of a chip or a bar. The light-emitter device 100 may include a substrate (not shown) and an active region 102, which may include an n-side portion that may include an n-type semiconductor material, one or more quantum wells 104 on top of the n-side portion, and a p-side portion that includes a p-type semiconductor material and is disposed on the one or more quantum wells 104. The light-emitter device 100 further includes one or more non-absorbing mirrors (NAMs). In this regard, the non-absorbing mirrors (NAMs) may be incorporated to reduce facet absorption, non-radiative recombination, bandgap shrinkage, and catastrophic optical damage (COD).

[0016]

[0022] Process flow 110 illustrates an exemplary process for adding a non-absorbing mirror (NAM), particularly when forming a NAM-based device (e.g., light emitter device 100). In step 111, a first epi growth is performed to provide an n-side region having a quantum well (QW) layer grown on top of the n-side region, and then growth of a p-side region may begin on top of the QW layer. To add the NAM, growth may be interrupted after the QW(s) and an initial waveguide is added. In this regard, in step 113, lithography and etching are performed to define the area where the NAM is to be added. Then, in step 115, a second epi growth may be performed to form the NAM. In this regard, the QWs may be etched on the emitter-side facet sides to define the NAM, and then the remainder of the p-side portion (epi) is grown on the entire wafer, resulting in a NAM on the front and back of the device—e.g., light (laser) can be emitted out the sides (right and left of the device as shown in process flow 110). The resulting refractive index change between the NAM and non-NAM regions can be calculated as follows: neff =3e -3, which can be quite large. The top view of a light emitter device incorporating a non-absorbing mirror (NAM) is shown in Figure 2.

[0017]

[0023] 2 shows an exemplary light emitter device including a non-absorbing mirror (NAM) from a top view showing various details thereof. Shown in FIG. 2 is light emitter device 200.

[0018]

[0024] The light emitter apparatus 200 may include a non-absorbing mirror (NAM). In this regard, the light emitter apparatus 200 may be substantially similar to the light emitter apparatus 100 of Figure 1. In particular, Figure 2 shows a top view of the light emitter apparatus 200—i.e., the light emitter apparatus 200 as viewed from above.

[0019]

[0025] The light emitter device 200 can include an active region having or forming an excitation active region 210 that is interrupted, i.e., where portions of the device's active region are removed (as described with respect to process flow 110) at the front—i.e., front facet (or “FM”) 220 and the back—i.e., back facet (or “BM”) 230 to form a non-absorbing mirror (NAM). Each of the FM 220 and BM 230 may be, for example, about 10 μm.

[0020]

[0026] In accordance with the present disclosure, light emitter devices (e.g., light emitter devices 100, 200) may be modified to incorporate refractive index (RI)-based engineering modifications for brightness enhancement and kink suppression. In various embodiments, such RI-based engineering modifications may include incorporating loss structures configured to enable enhanced brightness and kink suppression. For example, in light emitter devices incorporating non-absorbing mirrors (NAMs), these structures may be lateral loss structures incorporated along the sides of the pump active region 210 and between the NAMs. Examples of such embodiments, and various features or aspects associated therewith, are described in more detail below.

[0021]

[0027] Nevertheless, while various implementations described herein are directed to light-emitter devices incorporating non-absorbing mirrors (NAMs), the present disclosure is not limited to such devices, and solutions based on the present disclosure may be applied to any suitable light-emitter device. In this regard, similar results to those described herein may be achieved by introducing refractive index (RI)-based control by means other than QW removal and subsequent overgrowth, such as by etching features on the top surface of the emitter device that do not include any overgrowth.

[0022]

[0028] 3 shows an example light emitter device including a non-absorbing mirror (NAM) and a loss structure. Shown in FIG. 3 is a light emitter device 300.

[0029] Light emitter device 300 may be substantially similar to light emitter devices 100 and 200 described herein and, therefore, may include a non-absorbing mirror (NAM). Thus, light emitter device 300 has or forms an exciter active region 310 and may include an active region including quantum wells (QWs), where exciter active region 310 is interrupted—i.e., where the QW(s) are removed (as described with respect to process flow 110) at NAM facets, such as front facet (or “FM”) 320 at the front of the device and back facet (or “BM”) 330 at the rear of the device. However, light emitter device 300 may further include a loss structure 340.

[0023]

[0030] In this regard, as described above, in accordance with the present disclosure, the light emitter device may incorporate and / or otherwise be configured to utilize modifications related to refractive index (RI)-based engineering for brightness enhancement and kink suppression. The loss structure 340 may be designed and / or configured to realize such RI-based engineering modifications. In particular, the loss structure 340 may be configured to provide sufficient loss to achieve both brightness enhancement and kink suppression, and to do so in a cost-effective manner. For example, the loss structure (particularly the loss structure 340 shown in detail in FIG. 3 ) may include only a side pattern along at least a portion of the length of the active region—i.e., on both (or one) sides of the pump active region (e.g., pump active region 310 in the light emitter device 300). Implementing such a loss structure may require only a series of scatterers—i.e., a minimum of two repetitions of the features in the loss structure (which in the exemplary embodiment shown in FIG. 3 include dot-like features).

[0024]

[0031] In the embodiment shown in FIG. 3, the scatterers are implemented via etching of the active region followed by overgrowth and are present along the entire length of the device. In this particular example, dots are selectively etched to remove quantum wells on the bottom epi wafer of the device. As a result, the entire wafer surface is overgrown to obtain the final full epi structure, resulting in a final surface with minimal topography compared to possible alternative implementations that require deep trenches. This is the exact same process that can be used to realize non-absorbing mirrors (NAMs) on the front and rear facets of the emitter as described in U.S. Patent Application No. 17 / 249,916, filed March 18, 2021, and incorporated herein by reference in its entirety. The reduced topography and lack of special stabilization processing requirements can be significant advantages of this approach.

[0025]

[0032] Various aspects of the loss structure may be configured or tailored to achieve desired performance for brightness enhancement and kink suppression. For example, with reference to the embodiment shown in FIG. 3, an estimated refractive index (RI) variation (difference) of at least 0.0001 (e.g., about 0.003) between regions with and without an active region may be sufficient to introduce loss into the mode responsible for a visible power kink in an unpatterned device. Furthermore, a minimum of two scatterers may be required to fully suppress the kink; complete removal of the emitter-side active region or a single scatterer line results in a reduced discontinuity in the device's light-current (LI) curve, but not its complete elimination.

[0026]

[0033] Similarly, various characteristics of the loss structures (scatterers) may be set or adjusted to achieve desired performance for brightness enhancement and kink suppression. Such characteristics may include parameters related to the features themselves (e.g., their dimensions), spacing, fill factor, etc. In this regard, spacing, as used herein, includes the spacing (distance) between lines within the loss structures, the spacing (distance) between repeated features within each line in implementations where non-solid lines are used, and / or the spacing (distance) between the loss structures and the pump active region.

[0027]

[0034] For example, using a design similar to that shown in Figure 3 with respect to scatterer dimensions and spacing, desirable performance can be achieved by using dots and grooves with widths that are at least half the emission wavelength (e.g., 2 μm, 3 μm, 4 μm, or even larger for devices with emission wavelengths between 900 nm and 1000 nm), and by having the first row of scatterers located at least five times the emission wavelength (e.g., 15 μm, 20 μm, 30 μm, 40 μm, or even longer for devices with emission wavelengths between 900 nm and 1000 nm). Furthermore, devices with fill factors of up to 85% (e.g., 65%, 72%, 75%, or 80%) may be able to achieve the desirable benefits of the proposed solution.

[0028]

[0035] Nevertheless, while the loss structure 340 is shown as having a particular design—i.e., two rows on each side of dot-shaped scatterers meeting particular spacing criteria—the present disclosure is not limited to such an approach. Rather, the solution according to the present disclosure allows flexibility in the design of the side scatterers by allowing for different designs (e.g., rows of dots, stripes, etc.) and for varying the depth, periodicity, and spacing of the scatterers within the loss structure, as well as the distance between the loss structure and the pump active region, while maintaining the desired benefits of the proposed solution. An alternative loss structure is shown in and described with respect to FIG. 4.

[0029]

[0036] The use of the NAM loss structures described herein can provide significant advantages, such as those related to cost and compatibility. In this regard, because of the reliability of the front and rear facets, the NAM process is already in use, so adding such loss structures should not require a significant increase (if any) in cost, and should not require any additional processing or lithography steps to add the structure. Furthermore, as long as the fabricated scatterer provides a refractive index variation of at least 0.0001 (e.g., about 0.003) or more, the loss structure can function just as well with a deeper etch (with or without active region removal, and with or without overgrowth).

[0030]

[0037] 4 shows different exemplary loss structures that may be used in a light emitter device that includes a non-absorbing mirror (NAM). Shown in FIG. 4 are loss structures 400, 410, 420, and 430.

[0031]

[0038] A loss structure typically can include two or more lines of features. The lines can be solid (continuous) or can be lines of spaced features (e.g., at specific, equal intervals). In this regard, when non-solid lines are used, any suitable shape can be used. Various aspects and / or characteristics of the loss structure can be configured or adjusted to optimize performance. For example, the number of lines used in the loss structure can be adaptively selected, such as to optimize performance. Furthermore, the spacing between the lines (and / or, in implementations where non-solid lines are used, the spacing between repeated features in each line) and / or the spacing from the light-emitting region can be configured or adjusted to optimize performance. Furthermore, in some cases, in implementations where non-solid lines are used, the lines can be arranged such that the repeated features can be arranged in a zigzag pattern.

[0032]

[0039] For example, as shown in FIG. 4, loss structure 400 includes two lines of dot features (or simply "dots") (the dot features are zigzagged in the two lines as shown in FIG. 4). Loss structure 410 includes two solid (continuous) lines. Loss structure 420 includes three lines of dot features (or simply "dots") (the dot features are zigzagged in the three lines as shown in FIG. 4). Loss structure 430 includes two lines of hexagonal dots. Other shapes and / or numbers of lines are also possible.

[0033]

[0040] During operation, NAM loss structures, including dot arrays and / or multiple grooves, such as those shown in Figure 4, can demonstrate improved kink suppression behavior. For example, devices including fill factors greater than 50%, for example, can exhibit apparent discontinuities in the power-current characteristics for both continuous wave (CW) and pulsed / quasi-continuous wave (qCW) measurements in the absence of loss structures to impede the propagation of higher-order modes. In contrast, the introduction of NAM loss structures (scatterers) results in continuous, kink-free, and reproducible power curves under the measurement conditions. Furthermore, NAM loss structures can significantly improve and stabilize the slow-axis divergence of the emitter far field. This is shown in the graphs of Figures 5A-8.

[0034]

[0041] 5A-5B are graphs illustrating the optical power performance of an exemplary optical emitter device that does not include refractive index engineering on the emitter side. Shown in Figures 5A-5B are graphs 500 and 510 illustrating the optical power performance of an optical emitter device that does not include refractive index engineering.

[0035]

[0042] Each of graphs 500 and 510 includes data representing the optical power of an optical chip. In this regard, each of graphs 500 and 510 includes multiple plots corresponding to multiple different chips (e.g., chips 1-8), each including data points representing optical power in watts (W) (y-axis) as a function of current in amperes (A) (x-axis). In this regard, graph 500 includes data corresponding to continuous wave (CW) operation, while graph 510 includes data corresponding to quasi-continuous wave (qCW) operation. Chips 1-8 may incorporate different wafer designs, but all lack the loss structures described herein—i.e., no refractive index engineering on the emitter side.

[0036]

[0043] As shown in graphs 500 and 510, designs without emitter-side refractive index engineering exhibit a significant kink (discontinuity) in the light-to-current (LI) curve—i.e., a jump in power—in both continuous wave (CW) and quasi-continuous wave (qCW) operation.

[0037]

[0044] 6A-6B are graphs illustrating the optical power performance of an example optical emitter device having patterned refractive index variations on the emitter side. Shown in Figures 6A-6B are graphs 600 and 610 illustrating the optical power performance of an optical emitter device including refractive index engineering.

[0038]

[0045] Each of graphs 600 and 610 includes data representing the optical power of an optical chip. In this regard, each of graphs 600 and 610 includes multiple plots corresponding to multiple different chips (e.g., chips 1-9), each including data points representing optical power in watts (W) (y-axis) as a function of current in amperes (A) (x-axis). Chips 1-9 may incorporate different wafer designs that include the use of the loss structures described herein. For example, the similarly named chips in Figures 5A-5B and 6A-6B have the same wafer and fill factor as previous slides, but also include the additional loss structures described herein.

[0039]

[0046] As shown in graphs 600 and 610 (especially relative to graphs 500 and 510 in Figures 5A-5B), the design incorporating patterned refractive index variations exhibits no detectable kink in the light-to-current (LI) curve in both continuous wave (CW) and quasi-continuous wave (qCW) operation.

[0040]

[0047] Figure 7 is a graph illustrating the improvement in slow axis divergence performance when using a lossy structure. Shown in Figure 7 is a graph 700 illustrating the slow axis divergence at 95% power content of a light emitter device.

[0041]

[0048] Graph 700 includes data representing the slow axis divergence of an optical emitter device (laser). In this regard, graph 700 includes plots 710 and 720, each including data points representing the slow axis divergence angle (95% power content) in degrees (°) (y-axis) as a function of current in amperes (A) (x-axis), where plot 710 corresponds to an optical emitter device that does not include a loss structure and plot 720 corresponds to an optical emitter device that includes a structured NAM implemented in accordance with the present disclosure, e.g., a laser emitter that includes a NAM and a side loss structure.

[0042]

[0049] Graph 700 shows the improvement to the far-field slow-axis divergence as a result of the use of a NAM loss structure in an optical emitter device (e.g., an emitter) relative to an optical emitter device that does not include the loss structure. In other words, the data points captured in graph 700 allow for a performance comparison using devices with the same epitaxial structure, cavity length, fill factor, width, and coating of the pump active region to demonstrate the improvement obtained from the use of a NAM loss structure.

[0043]

[0050] In this regard, the data used in generating graph 700 may be obtained using devices with the same chip dimensions and including a NAM, but with or without a side loss structure, to allow for comparison between the use of a loss structure and the absence of such a structure. As shown by graph 700, the slow-axis divergence at both low and high currents shows significant improvement for the device including a NAM and a loss structure (e.g., a side loss structure) compared to a similar device (but without a loss structure). In particular, as shown by plots 710 and 720, the use of a NAM with a loss structure results in improved performance in terms of the slow-axis divergence angle (95%). For example, at a current of 46 A, the device including a NAM and a loss structure achieves a slow-axis divergence (angle) that is 0.9° narrower than a similar device (e.g., with the same epitaxial structure, cavity length, fill factor, width, and coating of the pump active region), while also stabilizing the far field at low current values.

[0044]

[0051] Figure 8 is a graph illustrating the improvement in luminance performance when using a lossy structure. Shown in Figure 8 is a graph 800 illustrating the luminance performance of a light emitter device.

[0052] Graph 800 includes data representing the brightness of an optical emitter device (laser). In this regard, graph 800 includes plots 810 and 820, each including data points representing brightness in Watts (W) (y-axis) in W / mm*mrad as a function of power in Watts (W) (x-axis), where plot 810 corresponds to an optical emitter device that does not include a loss structure and plot 820 corresponds to an optical emitter device that includes a structured NAM implemented in accordance with the present disclosure, e.g., a laser emitter that includes a NAM and a side loss structure.

[0045]

[0053] In this regard, the data used in generating graph 800 may be obtained using devices with the same chip dimensions and including a NAM, but with or without side loss structures, to allow for comparison between the use of loss structures and the absence of such structures. As shown in graph 800 (plots 810 and 820), the use of a NAM including a loss structure results in improved performance with respect to device brightness. In particular, the loss structure introduced by the NAM process can result in a significant increase in laser brightness across the entire current range. For example, as shown in graph 800, device brightness can be increased by approximately 13% at a 40 W rating.

[0046]

[0054] In accordance with the present disclosure, an exemplary light-emitter device includes a first region including a first semiconductor material, an active region disposed on the first region, the active region including a pumping active region between a front end and a rear end of the light-emitter device, and a plurality of loss structures disposed along at least a portion of at least one side of the pumping active region.

[0047]

[0055] In an exemplary embodiment, a plurality of loss structures are disposed between the front and back ends of the light emitter device.

[0056] In an exemplary embodiment, the multiple loss structures include two or more continuous etched lines.

[0048]

[0057] In an exemplary embodiment, the plurality of loss structures includes two or more lines of discontinuous etched features.

[0058] In an exemplary embodiment, the discontinuous features include etched indentations such as dots.

[0049]

[0059] In an exemplary embodiment, the plurality of loss structures includes two or more lines or columns, each line or column having a width that is at least half the emission wavelength of the light emitter device.

[0060] In an exemplary embodiment, the plurality of loss structures includes two or more lines or rows, and a first line or row of the plurality of loss structures is spaced apart a distance of at least five times the emission wavelength of the light emitter device.

[0050]

[0061] In an exemplary embodiment, the plurality of lossy structures are configured to provide a fill factor of 85% or less.

[0062] In an exemplary embodiment, the plurality of loss structures includes a first plurality of loss structures and a second plurality of loss structures, the first plurality of loss structures and the second plurality of loss structures being disposed on different sides of the pump active region.

[0051]

[0063] In an exemplary embodiment, the first plurality of loss structures and the second plurality of loss structures are identical.

[0064] In an exemplary embodiment, the first plurality of loss structures differs from the second plurality of loss structures with respect to at least one parameter or characteristic.

[0052]

[0065] In an exemplary embodiment, the loss structures are configured to ensure that predetermined optical performance criteria are met.

[0066] In an exemplary embodiment, the optical performance criteria includes providing a refractive index (RI) variation of at least 0.0001 for regions incorporating multiple loss structures.

[0053]

[0067] In an exemplary embodiment, the plurality of loss structures are configured to scatter the emitted light in one or more directions other than through the front and back ends of the light emitter device.

[0054]

[0068] In an exemplary embodiment, the active region includes a quantum well (QW).

[0069] In an exemplary embodiment, the light emitter device is an edge-emitting laser device.

[0070] An exemplary method of fabricating a light-emitter device according to the present disclosure includes growing a first portion including a first region including a first semiconductor material and an active region disposed on the first region, followed by selectively etching the active region to form a pump active region between a front end and a rear end of the light-emitter device, and etching a plurality of loss structures along at least a portion of at least one side of the pump active region.

[0055]

[0071] In an exemplary embodiment, the method further includes disposing a plurality of loss structures between the front end and the back end of the light emitter device.

[0072] In an exemplary embodiment, etching the plurality of loss structures includes etching two or more continuous etched lines.

[0056]

[0073] In an exemplary embodiment, etching the plurality of loss structures includes etching two or more lines of discontinuous etched features.

[0074] In an exemplary embodiment, the plurality of loss structures includes two or more lines or columns, and further includes etching the plurality of loss structures such that a width of each line or column is at least half the emission wavelength of the light emitter device. In an exemplary embodiment, the plurality of loss structures includes two or more lines or columns, and etching the plurality of loss structures includes etching a first line or column of the plurality of loss structures a distance of at least five times the emission wavelength of the light emitter device.

[0057]

[0075] In an exemplary embodiment, the method further includes etching the plurality of lossy structures to result in a fill factor of 85% or less.

[0076] In an exemplary embodiment, etching the plurality of loss structures includes etching a first plurality of loss structures and a second plurality of loss structures, the first plurality of loss structures and the second plurality of loss structures being disposed on different sides of the pump active region.

[0058]

[0077] In an exemplary embodiment, the first plurality of loss structures and the second plurality of loss structures are identical.

[0078] In an exemplary embodiment, the first plurality of loss structures differs from the second plurality of loss structures with respect to at least one parameter or characteristic.

[0059]

[0079] In an exemplary embodiment, the method further includes configuring the plurality of loss structures to ensure that predetermined optical performance criteria are met.

[0080] In an exemplary embodiment, the optical performance criteria includes providing a refractive index (RI) variation of at least 0.0001 for regions incorporating multiple loss structures.

[0060]

[0081] In an exemplary embodiment, the method further includes configuring the plurality of loss structures to be configured to scatter the emitted light in one or more directions other than through the front and back ends of the light emitter device.

[0061]

[0082] In an exemplary embodiment, the method further includes configuring at least a portion of the active region as a quantum well (QW).

[0083] As used herein, "and / or" means any one or more of the items in the list joined by "and / or." As an example, "x and / or y" means any element of the ternary set {(x), (y), (x, y)}. In other words, "x and / or y" means "one or both of x and y." As another example, "x, y, and / or z" means any element of the septenary set {(x), (y), (z), (x, y), (x, z), (y, z), (x, y, z)}. In other words, "x, y, and / or z" means "one or more of x, y, and z." As used herein, the term "exemplary" means serving as a non-limiting example, instance, or illustration. As used herein, the terms "for example" and "eg" represent a list of one or more non-limiting examples, instances, or illustrations.

[0062]

[0084] While the present methods and / or systems have been described with reference to certain specific implementations, it will be recognized by those skilled in the art that various modifications can be made and equivalents may be substituted without departing from the scope of the present methods and / or systems. Additionally, many modifications may be made to adapt a particular situation or material to the teachings of the present disclosure without departing from the scope of the present disclosure. Therefore, it is not intended that the present methods and / or systems be limited to the particular implementations disclosed, but rather that the present methods and / or systems will include all implementations falling within the scope of the appended claims.

Claims

1. 1. A light emitter device comprising: a first region including a first semiconductor material; an active region disposed on the first region, the active region including an excitation active region between a front end and a rear end of the light emitter device; a plurality of loss structures disposed along at least a portion of at least one side of the pump active region, the active region including quantum wells (QWs), the plurality of loss structures being filled with a second semiconductor material in a layer of the quantum wells (QWs); 1. A light emitter device comprising:

2. 2. The optical emitter device of claim 1, wherein the plurality of loss structures are disposed between the front end and the back end of the optical emitter device.

3. 10. The light emitter device of claim 1, wherein the plurality of loss structures comprises two or more continuous etched lines.

4. 10. The light emitter device of claim 1, wherein the plurality of loss structures comprises two or more lines of discontinuous etched features.

5. 5. The light emitter device of claim 4, wherein the discontinuous features comprise etched indentations such as dots.

6. 10. The light emitter device of claim 1, wherein the plurality of loss structures comprises two or more lines or columns, each line or column having a width that is at least half the emission wavelength of the light emitter device.

7. 10. The optical emitter device of claim 1, wherein the plurality of loss structures comprises two or more lines or rows, and a first line or row of the plurality of loss structures is spaced apart by a distance of at least five times the emission wavelength of the optical emitter device.

8. 10. The optical emitter device of claim 1, wherein the plurality of lossy structures are configured to provide a fill factor of 85% or less.

9. 2. An optical emitter device according to claim 1, wherein the plurality of loss structures includes a first plurality of loss structures and a second plurality of loss structures, the first plurality of loss structures and the second plurality of loss structures being disposed on different sides of the excited active region.

10. 10. The light emitter device of claim 9, wherein the first plurality of loss structures and the second plurality of loss structures are identical.

11. 10. The light emitter device of claim 9, wherein the first plurality of loss structures differ from the second plurality of loss structures with respect to at least one parameter or characteristic.

12. 10. The optical emitter device of claim 1, wherein the plurality of loss structures are configured to ensure that predetermined optical performance criteria are met.

13. 13. The optical emitter device of claim 12, wherein the optical performance criteria includes providing a refractive index (RI) variation of at least 0.0001 for a region incorporating the plurality of loss structures.

14. 10. The light emitter device of claim 1, wherein the plurality of loss structures are configured to scatter emitted light in one or more directions other than through the front and back ends of the light emitter device.

15. 10. The optical emitter device of claim 1, wherein the optical emitter device is an edge-emitting laser device.

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