Laser array with emitter isolation

Abstract

The laser assembly 10 includes a substrate 22, a plurality of spaced lasers 20 grown on the substrate 22, and an electrical connector assembly 14. The lasers 20 are individually inspected to identify whether the inspected lasers 20 are good lasers 20a or bad lasers 20b. The electrical connector assembly 14 is adapted to electrically connect a power supply source 16 to the identified good lasers 20a and to not electrically connect the identified bad lasers 20b to the supply source 16. Thus, the identified bad lasers 20b are electrically isolated from the supply source 16.

Description

Technical Field

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 389,682, filed Jul. 15, 2022, entitled “LASER ARRAY WITH EMITTER ISOLATION”. To the extent permitted, the content of U.S. Provisional Application No. 63 / 389,682 is incorporated herein.

Background Art

[0002] Multiple lasers can be grown on a semiconductor wafer, and the wafer can be diced into multiple laser arrays, each laser array having multiple lasers. Depending on the type of laser, it can be very difficult to accurately grow each of the lasers on the wafer. This significantly reduces the yield of usable laser arrays from the semiconductor wafer. As a result, it is necessary to increase the yield of usable laser arrays from the semiconductor wafer.

Summary of the Invention

[0003] A laser assembly provided herein includes a substrate, a laser array including a plurality of spaced-apart lasers grown on the substrate, and an electrical connector assembly. In one implementation, at least two of the lasers are individually inspected to identify whether the inspected lasers are good lasers or bad lasers. Further, the electrical connector assembly is adapted to electrically connect a power source to the identified good lasers and to electrically isolate the identified bad lasers.

[0004] In other words, the lasers of the laser array can be analyzed and individually inspected to individually identify "good lasers" and "bad lasers". Subsequently, the laser array and / or the electrical connector assembly may be modified and / or adjusted to electrically isolate the identified lasers. Thus, the bad lasers are identified and isolated. As a result, the bad lasers do not heat or short-circuit the laser array, and the laser array becomes usable and more reliable. This increases the yield of usable laser arrays.

[0005] In one implementation, the electrical connector assembly includes a non-conductive layer disposed in at least one path of the identified bad lasers. In a particular implementation, each of the identified bad lasers can include an electrical pad, and the non-conductive layer can be a dielectric disposed on the electrical pad.

[0006] The non-conductive layer may be selected from the group including silicon dioxide (SiO2), aluminum oxide (Al2O3), silicon nitride (Si3N4), or titanium oxide (TiO).

[0007] The dielectric may be formed using a shadow mask using a line of sight film formation technique.

[0008] In a particular implementation, at least one of the lasers is a quantum cascade gain medium.

[0009] In one implementation, each of the plurality of lasers is individually inspected to identify whether the inspected laser is a good laser or a bad laser.

[0010] Furthermore, the electrical connector assembly may be adapted to electrically connect the source to all of the identified good lasers and to electrically isolate all of the identified bad lasers.

[0011] In another implementation example, the laser assembly also includes a substrate, a plurality of spaced lasers grown on the substrate, and an electrical connector assembly. In this implementation example, at least two of the lasers are individually inspected to identify whether the inspected laser is a good laser or a bad laser. Further, at least a portion of one of the bad lasers is removed after being identified as a bad laser. Further, the electrical connector assembly is adapted to electrically connect the supply source to the identified good lasers and electrically isolate the identified bad lasers.

[0012] In one implementation example, the removal is achieved by ablation using a laser or an ion beam. Alternatively, the removal can be achieved by chemical etching.

[0013] Further, the laser assembly can further include a protective layer disposed over the identified good lasers to protect the good lasers during the removal of a portion of one of the bad lasers.

[0014] In a particular implementation example, each of the plurality of lasers is individually inspected to identify whether the inspected laser is a good laser or a bad laser. In this design, at least a portion of each of the bad lasers is removed after being identified as a bad laser.

[0015] In another implementation example, a method for fabricating a laser assembly powered by a supply source includes providing a substrate including a laser array grown on the substrate, the laser array having a plurality of spaced lasers, individually inspecting at least two of the lasers to identify whether the inspected lasers are good lasers or bad lasers, electrically connecting the supply source to the identified good lasers, and not electrically connecting the identified bad lasers to an electrical connector assembly.

[0016] In yet another implementation example, a method for fabricating a laser assembly powered by a power source includes providing a substrate including a laser array grown on the substrate, the laser array having a plurality of spaced-apart lasers; individually inspecting at least two of the lasers to identify whether the inspected lasers are good lasers or bad lasers; electrically connecting the power source to the identified good lasers; and not electrically connecting the identified bad lasers to an electrical connector assembly.

[0017] The novel features of the invention and the invention itself will be best understood from the accompanying drawings in conjunction with the accompanying description, both as to its structure and its operation. In the drawings, like reference characters refer to like parts.

Brief Description of the Drawings

[0018]

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Embodiments of the Invention

[0019] FIG. 1 is a simplified schematic side view of (i) a laser assembly 10 including a laser array 12 and an electrical connector assembly 14, (ii) a source 16 (illustrated as a box), and (iii) a control system 18 (illustrated as a box) that controls the operation of the laser assembly 10. In this implementation example, the laser array 12 includes a plurality of spaced-apart individual lasers 20 (each illustrated as a box) grown on a substrate 22.

[0020] For each of the embodiments disclosed herein, the number of lasers 20 within the laser array 12 can be varied to conform to the output requirements of the laser assembly 10. In the non-exclusive implementation example of FIG. 1, the laser array 12 includes 23 spaced-apart lasers 20. Alternatively, the laser array 12 may be designed to have a greater or fewer number of spaced-apart lasers 20 than 23. As an alternative non-exclusive implementation example, the laser array 12 may be designed to include at least 5, 8, 10, 15, 20, 25, 30, 40, 50, 60, 70, 80, 90, 100, 120, 150, or 200 individual lasers 20 on a common substrate 22.

[0021] Generally, for a given design of the laser array 12, the potential power output of the laser array 12 will increase as the number of lasers 20 within the laser array 12 increases. Thus, the number of lasers 20 can be adjusted to suit the desired application and desired power output of the laser assembly 10.

[0022] The design of each laser 20 can also be varied to achieve the output requirements (e.g., wavelength and optical power) of the laser assembly 10. As an alternative non-exclusive example, one or more (e.g., all) of the lasers 20 may be a quantum cascade gain medium, a quantum well gain medium, or another type of gain medium.

[0023] As a non-exclusive example, each of the lasers 20 may be designed to generate from about 1 to 2 watts. However, other values are possible. As an alternative example, each of the lasers 20 may be designed to generate at least about 0.5 watts, 1 watt, 2 watts, or 3 watts.

[0024] Note that each of the lasers 20 may alternatively be referred to as an emitter or gain medium. Further, any of the lasers 20 may be referred to as the first, second, third, fourth, etc. laser.

[0025] FIG. 1 shows the exit surface 24 of each laser 20, and each functional laser 20 emits light from the output surface 24 when sufficiently powered by the source 16. Alternatively, one or more of the lasers 20 may be designed to emit from two surfaces.

[0026] The type of the substrate 22 can be changed to be compatible with the design of the laser 20. As a non-exclusive alternative example, the substrate 22 may be made of indium phosphide (''InP''), silicon, or other suitable materials.

[0027] In a particular design, the lasers 20 are grown on a common semiconductor wafer (not shown). Subsequently, the wafer and the lasers 20 are cut into a plurality of bars, and each bar defines one laser array 12. The number of bars within a given semiconductor wafer depends on many factors including (but not limited to) the desired number of lasers 20 within the laser array 12 and / or the size of the semiconductor wafer. As a non-exclusive example, the wafer may be cut into at least 2, 10, 20, 30, 50, 100, 1000, or more laser arrays 12.

[0028] As provided herein, depending on the type of laser 20, it is often very difficult to accurately grow each of the lasers 20 on the wafer. As a result, one or more of the lasers 20 may be weak or inoperable (collectively referred to as "defective lasers"). Each weak laser 20 may generate a significant amount of heat when powered by the power source 16. This can have an adverse effect on the laser array 12, and the weak laser 20 is more likely to subsequently fail. An inoperable laser 20 may cause a short circuit in the entire laser array 12. Therefore, weak lasers and inoperable lasers 20 can significantly reduce the yield of usable laser arrays 12 from semiconductor wafers.

[0029] In summary, as provided herein, the lasers 20 of the laser array 12 can be analyzed and individually inspected to individually identify "good lasers" 20a and "defective lasers" 20b (represented by "x") within the laser array 12. Subsequently, the laser array 12 and / or the electrical connector assembly 14 are modified and / or adjusted to electrically isolate the defective laser 20b. Therefore, the defective laser 20b is identified and isolated. As a result, the defective laser 20b neither heats nor shorts the laser array 12, and the laser array 12 becomes usable. This increases the yield of usable laser arrays 12 from the wafer.

[0030] In other words, the present invention teaches that the defective laser 20b can be electrically isolated, and the laser array 12 can still be used as long as the laser array 12 contains a sufficient number of good lasers 20a. For example, in a simplified example, the optical power for a desired application can be generated by 20 lasers 20 within the laser array 12. In FIG. 1, the lasers 20 have been individually inspected, and the laser array 12 includes 21 "good lasers" 20a and two "defective lasers" 20b. In this example, the laser array 12 is acceptable because there are 20 or more good lasers 20a. In other words, in this example, the laser array 12 is acceptable because there are three or fewer defective lasers 20b.

[0031] The number of good lasers 20a and defective lasers 20b within a given laser array 12 will vary depending on the manufacturing process. As an alternative non-exclusive example, a grown laser array 12 can include (i) at least 5, 8, 10, 15, 20, 25, 30, 40, 50, 60, 70, 80, 90, 100, 120, 150, or 200 individual good lasers 20a, and / or (ii) at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 defective lasers 20b. Note that any number of defective lasers 20b can be isolated regardless of how many defective lasers there are. Generally speaking, as the total number of lasers 20 increases, the number of defective lasers 20b also increases. As a non-exclusive extreme example, the laser array 12 can include 200 good lasers 20a and 200 defective lasers 20b.

[0032] As provided herein, inspection and processing can be used to identify and isolate defective laser(s) 20b in order to obtain high reliability and yield for the laser array 12. This prevents the defective laser(s) 20b from becoming a failure point in the laser array 12. This is particularly beneficial for quantum cascade arrays with a large number of emitters where embedded heterostructure processing makes it difficult to obtain high yields.

[0033] In summary, the present design improves the reliability and yield of the laser array 12 by identifying and isolating the defective emitter 20b.

[0034] The electrical connector assembly 14 electrically connects the laser array 12 to the power source 16. In FIG. 1, the electrical connector assembly 14 includes (i) an upper first conductor plate 14a electrically connected to each of the good lasers 20a, (ii) a lower second conductor plate 14b electrically connected to each of the good lasers 20a, (iii) a first connector 14c electrically connecting the first conductor plate 14a to the power source 16, and (iv) a second connector 14d electrically connecting the second conductor plate 14b to the power source 16. Alternatively or additionally, the electrical connector assembly 14 can include one or more electrical leads and / or connectors. In one non-exclusive design, the electrical connector assembly 14 connects the good lasers 20a to the power source 16 in parallel such that the good lasers 20a emit light substantially simultaneously. Alternatively, for example, the electrical connector assembly 14 may electrically connect the good lasers 20a to the power source 16 in series.

[0035] The power source 16 transmits power, such as current and / or voltage, to the laser array 12 via the electrical connector assembly 14. For example, the power source 16 may be pulsed or constant.

[0036] The control system 18 controls the operation of the power source 16 and the power output of the laser array 12. The control system 18 can include one or more processors 18A and / or electronic data storage devices 18B. Note that the control system 18 is illustrated as a single central processing system in FIG. 1. Alternatively, the control system 18 may be a distributed processing system.

[0037] FIG. 2 is a simplified top view of another implementation example of a laser array 212 including 18 spaced lasers 220. In one non-exclusive embodiment, each laser 220 of the laser array 212 is individually inspected after the laser array 212 is cut from the wafer and before being connected to the electrical connector assembly 14 (illustrated in FIG. 1).

[0038] In FIG. 2, one of the lasers 220 is highlighted and labeled 220c because power is being transmitted to this activated laser 220c and it is being individually inspected. In FIG. 2, the dashed arrow 220d represents the output beam (e.g., a laser beam) generated by the activated laser 220c.

[0039] Further, FIG. 2 illustrates a detector assembly 226 (shown as a box) used to inspect the individual lasers 220. For example, the detector assembly 226 may be a sensor that measures the power output of the generated output beam 220d to inspect the individual activated lasers 220c.

[0040] In one embodiment, the lasers 220 are individually powered continuously and individually inspected to measure the respective power output of each laser 220. Subsequently, the optical power output of each laser 220 may be used to evaluate and distinguish between good lasers 20a (see FIG. 1) and bad lasers 20b (see FIG. 1). In this design, prior to packaging, each emitter 220 is individually probed and inspected for electro-optical performance.

[0041] Alternatively, the detector assembly 226 may be designed to power a plurality (e.g., all) of the lasers 220 simultaneously, individually measure the optical power output of the powered lasers 220, individually determine the corresponding electro-optical performance, and identify the powered lasers 220 as either good lasers 20a or bad lasers 20b.

[0042] Note that other methods than optical power output can be used to distinguish between the good laser 20a and the bad laser 20b. As a non - exclusive example, the resistance measurement value or local temperature spike of an individual laser can be utilized to distinguish between the good laser 20a and the bad laser 20b.

[0043] Figure 3 is a graph illustrating the optical power output of a plurality of activated (tested) lasers in a laser array. In this example, the laser array includes 40 separated lasers. As shown in Figure 3, in this non - exclusive example, laser number 4, laser number 18, and laser number 34 generate significantly less optical power than the other lasers. In this example, laser numbers 4, 18, and 34 can be labeled as bad lasers, and the remaining 37 lasers can be labeled as good lasers. As provided herein, since these bad lasers are prone to excessive heating and early failure, these bad lasers are electrically isolated (not electrically connected to the power source 16 (illustrated in FIG. 1)).

[0044] In this design, (i) the bad lasers have a relatively low optical power output, and (ii) the good lasers have a relatively high optical power output. Note that the difference in optical power output between the good lasers and the bad lasers can vary. As a non - exclusive example, a laser can be labeled and identified as a "bad laser" if its optical output power is less than 90, 80, 70, 60, 50, 40, 30, 20, or 10 percent of the designed optical output power of the laser.

[0045] Note also that the term "bad laser" includes both lasers that are weak (e.g., have a relatively low optical output power) when powered by the power source 16 and lasers that do not operate (e.g., do not generate an optical output power) when powered by the power source 16.

[0046] FIG. 4 is a more detailed side view of a simplified small laser array 412. In this simplified example, the laser array includes a substrate 422 and only two individual lasers 420. Note that the laser array 412 is typically designed and constructed to include more than two individual lasers on the substrate 422 as described above. These additional lasers (not shown) may be similar to the lasers 420 shown.

[0047] During the growth process, multiple layers are continuously grown on the substrate 422. Subsequently, a portion of this material is removed and filled with insulating regrowth 428 to form individual gain regions 420a for each laser 420. Note that the laser array 412 of FIG. 4 has an epi side 412a and an opposing base side 412b.

[0048] Furthermore, as shown in FIG. 4, the laser array 412 can include an insulating layer 430 that covers and separates each laser 420, and a separate electrical contact pad 432 for each of the lasers 420. In this design, (i) the insulating layer 430 includes a separate layer aperture 430a disposed over the gain region 420a of each laser 420, (ii) each electrical contact pad 432 is disposed on the insulating layer 430, and (iii) each electrical contact pad 432 is electrically connected to the corresponding gain region 420a through the corresponding layer aperture 430a.

[0049] In this non-exclusive example, two lasers 420 have been inspected and determined to be good lasers.

[0050] FIG. 5 is a simplified side view of the laser array 412 of FIG. 4 electrically connected to an electrical connector assembly 514 with the epi side 412a facing down.

[0051] In the non-exclusive implementation example of FIG. 5, the electrical connector assembly 514 includes a first conductor plate 514a electrically connected to the base side surface 412b of the laser array 412, and a second conductor plate 514b electrically connected to the electrical contact pad 432 (e.g., by solder 534). In this design, the conductor plates 514a, 514b are electrically connected to the power source 16 (shown in FIG. 1).

[0052] As provided above, in this example, the two lasers 420 shown have been inspected and determined to be good lasers. Therefore, in the laser array 412 shown in FIG. 5, the two lasers 420 are electrically connected to the power source 16 via the electrical connector assembly 514. Using this design, the power from the power source 16 can drive both lasers 420.

[0053] Furthermore, in the design of FIG. 5, the second conductor plate 514b can function as a heat sink for removing heat from the laser array 412, either additionally or optionally.

[0054] FIG. 6 is a simplified side view of a different small laser array 612 including a substrate 622 and two lasers 620. Note that the laser array 612 is typically designed and constructed to include more than two individual lasers 620 on the substrate 622 as described above. These additional lasers (not shown) may be similar to the lasers 620 shown.

[0055] As provided herein, during the growth process, multiple layers are continuously grown on the substrate 622, a portion of this material is removed, and filled with an insulating regrowth 628 to form the individual lasers 620.

[0056] Furthermore, as shown in FIG. 6, the laser array 612 can include an insulating layer 630 that covers and separates each laser 620, and a separate electrical contact pad 632 for each of the lasers 620.

[0057] In this non-exclusive example, two lasers 620 were inspected, and it was determined that the left laser 620 was a good laser 620a (e.g., sufficient optical power output), and the right laser 620 was a bad laser 620b (e.g., insufficient optical power output).

[0058] In one non-exclusive implementation, as provided herein, each bad laser 620b may be electrically isolated using a separate non-conductive layer 636 disposed in at least one path of the identified bad lasers 620b. In FIG. 6, the non-conductive layer 636 is an isolation dielectric cover disposed on the electrical contact pad 632 of the bad laser 620b. Using this design, electrical isolation of the identified bad laser 620b is achieved by incorporating (disposing) the non-conductive layer 636 on the identified bad laser 620b. In other words, the non-conductive layer 636 suppresses the flow of power from the power source 16 (shown in FIG. 1) through the bad laser 620b to electrically isolate the bad laser 620b, and enables the flow of power through the good laser 620a. In this design, electrical isolation of each bad laser 620b can be achieved by incorporating the non-conductive layer 636 on the identified bad laser 620b.

[0059] As a result, the electrical connector assembly 514 (shown in FIG. 5) electrically connects the power source 16 to the identified good laser 620a and electrically isolates one or more identified bad lasers 620b.

[0060] The design of the non-conductive layer 636 can be changed. In a particular non-exclusive example, the non-conductive layer 636 is a dielectric pad disposed on the electrical contact pad 632 (e.g., selectively deposited). As an alternative non-exclusive example, the dielectric can be selected from the group including SiO2, Al2O3, Si3N4, or TiO.

[0061] As a non-exclusive example, the dielectric can be formed using a shadow mask using line-of-sight film formation techniques such as evaporation or sputtering. Alternatively, the non-conductive layer 636 may be a small cap adhered over the electrical contact pads 632 of the identified defective laser 620b.

[0062] FIG. 7 is a simplified side view of another different laser array 712 including a substrate 722 and five individual lasers 720. Note that the laser array 712 is typically designed and constructed to include more than five individual lasers 720 on the substrate 722 as described above. These additional lasers (not shown) may be similar to the illustrated lasers 720.

[0063] In FIG. 7, the laser array 712 is electrically connected to an electrical connector assembly 714 with the epi side 712a facing down.

[0064] In this example, the laser array 712 includes five separate lasers 720 which, for convenience, may be labeled, from left to right, (i) a first laser 720-1, (ii) a second laser 720-2, (iii) a third laser 720-3, (iv) a fourth laser 720-4, and (v) a fifth laser 720-5. As provided herein, the lasers 720 are individually inspected. As an example, when inspected, (i) the first, third, and fourth lasers 720-1, 720-3, 720-4 are determined to be good lasers 720a and labeled, and (ii) the second and fifth lasers 720-2, 720-5 are determined to be defective lasers 720b and labeled.

[0065] FIG. 7 illustrates two alternative ways to electrically isolate the defective lasers 720-2, 720-5 from a source 16 (shown in FIG. 1) and electrically connect the good lasers 720-1, 720-3, 720-4 to the source 16.

[0066] More specifically, in this non-exclusive example, (i) a non-conductive layer 736 is added on the electrical pad 732 of the second laser 720-2 to electrically isolate the defective second laser 720-2, and (ii) a portion of the fifth laser 720-5 is physically removed and filled with an electrical insulating material 738. Using this design, electrical isolation of the second laser 720-2 is achieved by addition (e.g., non-conductive layer 736), and electrical isolation of the fifth laser 720-5 is achieved by subtraction, e.g., removing a portion of the laser so as not to bond it. For example, the removal can be achieved using a cutting device 740 (illustrated as a box) that generates a cutting laser beam or an ion beam. Alternatively, the cutting device 740 can use chemical etching to remove at least a portion of the defective laser 720b (e.g., the fifth laser 720-5).

[0067] In the non-exclusive implementation example of FIG. 7, the electrical connector assembly 714 includes (i) a first conductor plate 714a electrically connected to each of the base side surface 712b of the laser array 712 and the lasers 720, and (ii) a second conductor plate 714b electrically connected to the good laser 720a via the solder 734 and electrically isolated from the defective laser 720b. In this design, (i) the second conductor plate 714b is electrically connected (e.g., by solder) to the electrical contact pads 732 of the first, third, and fourth lasers 720-1, 720-3, 720-4, and (ii) the second conductor plate 714b is not electrically connected to the second and fifth lasers 720-2, 720-5.

[0068] Therefore, in the laser array 712 illustrated in FIG. 7, (i) the first, third, and fourth lasers 720-1, 720-3, 720-4 are electrically connected to the power source 16, and (ii) the second and fifth lasers 720-2, 720-5 are electrically isolated from the power source 16. Using this design, the power from the power source 16 (illustrated in FIG. 1) supplies power only to the first, third, and fourth lasers 720-1, 720-3, 720-4.

[0069] FIG. 8 is a simplified side view of yet another implementation example of a laser array 812 including a substrate 822 and two individual lasers 820 with the epi-side 812a facing down. Note that the laser array 812 is typically designed and constructed to include more than two individual lasers 820 grown on the substrate 822 as described above. These additional lasers (not shown) may be similar to the illustrated lasers 820.

[0070] In a non-exclusive implementation example of FIG. 8, the electrical connector assembly 814 includes a first conductor plate 814a electrically connected to the base side 812b of the laser array 812 and a second conductor plate 814b electrically connected to the electrical contact pad(s) 832 (e.g., by solder 834).

[0071] In this example, the two separate lasers 820 may be labeled, from left to right, (i) a first laser 820-1 and (ii) a second laser 820-2. Further, the two illustrated lasers 820 have been inspected, and it has been determined that the first laser 820-1 is a good laser 820a and the second laser 820-2 is a bad laser 820b. As shown in FIG. 8, a portion of the second laser 820-2 has been removed, for example, using a cutting device 740 (shown in FIG. 7), creating a void 838 in the second laser 820-2. This void 838 may optionally be filled with an electrically insulating material (not shown in FIG. 8).

[0072] In FIG. 8, (i) the second conductor plate 814b is electrically connected to the electrical contact pad 832 of the first laser 820-1 (e.g., by solder 834), and (ii) the second conductor plate 814b is not electrically connected to the second laser 820-2. Thus, using this design, the power from the source 16 (shown in FIG. 1) drives only the first laser 820-1.

[0073] In certain implementation examples, optionally, prior to removing a portion of the (one or more) defective lasers 820b, in order to protect the good laser 820a during the removal process, the electrical contact pads 832 of the good laser 820a can be covered with a protective coating (not shown). For example, the protective coating can include a parylene masking (or photoresist layer) to protect the good laser 820a from ion / laser milling. Subsequently, after the material has been removed from the defective laser 820b, the protective coating can be removed. For example, the protective coating can be removed by etching using a shadow mask with a line-of-sight etching technique such as reactive ion etching or ion milling, such that the good laser 820a is no longer electrically isolated.

[0074] Additionally and / or optionally, the ends of the laser array 814 can also be coated with a protective coating to prevent short circuits on the sidewalls.

[0075] In summary, as provided herein, the defective lasers are electrically isolated from the electrical connector assembly. For example, (i) one or more of the defective lasers can be electrically isolated using an additive process, such as a non-conductive layer, and / or (ii) one or more of the defective lasers can be electrically isolated using a subtractive process, such as ablation of the defective lasers.

[0076] The specific systems illustrated and disclosed herein are fully capable of achieving the objectives and providing the advantages described above, but they merely illustrate the presently preferred embodiments of the invention and are not intended to limit any details of the construction or design shown herein other than those described in the appended claims.

Claims

1. A laser assembly powered by a power source, comprising: a substrate; a laser array including a plurality of spaced lasers grown on the substrate, wherein at least two of the lasers are individually inspected to identify whether the inspected lasers are good lasers or bad lasers, and the laser array includes the identified good lasers and the identified bad lasers; an electrical connector assembly adapted to electrically connect the power source to the identified good lasers and electrically isolate the identified bad lasers; A laser assembly comprising the above components.

2. The laser assembly according to claim 1, wherein the electrical connector assembly includes a non-conductive layer disposed in the path of the identified bad lasers.

3. The laser assembly according to claim 2, wherein the identified bad lasers include electrical pads, and the non-conductive layer is a dielectric disposed on the electrical pads.

4. The laser assembly according to claim 3, wherein the non-conductive layer is selected from the group including silicon dioxide, aluminum oxide, silicon nitride, and titanium oxide.

5. The laser assembly according to claim 3, wherein the dielectric is formed using a shadow mask by a line-of-sight deposition technique.

6. The laser assembly according to any one of claims 1 to 5, wherein at least one of the lasers is a quantum cascade gain medium.

7. The laser assembly according to claim 1, wherein each of the lasers is individually inspected to identify whether the inspected laser is a good laser or a bad laser, and the laser array includes a plurality of identified good lasers.

8. The laser assembly according to claim 7, wherein the electrical connector assembly is adapted to electrically connect the power source to each of the identified good lasers and electrically isolate each of the identified bad lasers.

9. The laser assembly according to claim 1, wherein each of the lasers is individually inspected to identify whether the inspected laser is a good laser or a bad laser, and the laser array includes a plurality of identified bad lasers.

10. A laser assembly powered by a power source, comprising: a substrate; A laser array including a plurality of spaced lasers grown on the substrate, wherein at least two of the lasers are individually inspected to identify whether the inspected lasers are good lasers or bad lasers, the laser array including the identified good lasers and the identified bad lasers, and at least a portion of the identified bad lasers being removed after being identified as bad lasers. An electrical connector assembly adapted to electrically connect the supply source to the identified good lasers and electrically isolate the identified bad lasers. A laser assembly comprising the above.

11. The laser assembly according to claim 10, wherein the removal is achieved by ablation.

12. The laser assembly according to claim 10, wherein the removal is achieved by chemical etching.

13. The laser assembly according to claim 10, further comprising a protective layer disposed over the identified good lasers to protect the identified good lasers during removal of the portion of the identified bad lasers.

14. Each of the lasers is individually inspected to identify whether the inspected laser is a good laser or a bad laser, and the laser array includes a plurality of identified good lasers and a plurality of identified bad lasers.

15. At least a portion of each of the identified bad lasers is removed after being identified as bad lasers.

16. The electrical connector assembly includes a non-conductive layer disposed in a path of at least one of the identified bad lasers.

17. A method for fabricating a laser assembly powered by a supply source, comprising: Providing a substrate including a laser array grown on the substrate, the laser array having a plurality of spaced lasers; Individually inspecting at least two of the lasers to identify whether the inspected lasers are good lasers or bad lasers, the laser array including the identified good lasers and the identified bad lasers. Electrically connecting the supply source to the identified good lasers and not electrically connecting the identified bad lasers to the electrical connector assembly, A method comprising. **Claim 18** The method according to claim 17, wherein electrically connecting comprises disposing a non-conductive layer in the path of the identified bad lasers. **Claim 19** The method according to claim 18, wherein the identified bad lasers include electrical pads and the non-conductive layer is a dielectric disposed on the electrical pads after individual inspection. **Claim 20** The method according to claim 17, wherein providing a substrate includes at least one of the lasers being a quantum cascade gain medium. **Claim 21** The method according to claim 17, wherein individually inspecting includes individually inspecting each of the lasers to identify whether the inspected laser is a good laser or a bad laser, and the laser array includes a plurality of identified good lasers and a plurality of identified bad lasers. **Claim 22** The method according to claim 21, wherein electrically connecting includes electrically connecting the supply source to each of the identified good lasers and electrically isolating each of the identified bad lasers. **Claim 23** A method for fabricating a laser assembly powered by a supply source, Providing a substrate including a laser array grown on the substrate, the laser array having a plurality of spaced-apart lasers, Individually inspecting at least two of the lasers to identify whether the inspected lasers are good lasers or bad lasers, the laser array including identified good lasers and identified bad lasers, Electrically connecting the supply source to the identified good lasers and not electrically connecting the identified bad lasers to the electrical connector assembly, Removing at least a portion of one of the identified bad lasers, Electrically connecting the supply source to the identified good lasers and electrically isolating the identified bad lasers from the electrical connector assembly, A method comprising. **Claim 24** The method according to claim 23, wherein removing is achieved by ablation. **Claim 25** The method according to claim 23, wherein the removal is achieved by chemical etching. **Claim 26** The method according to claim 23, further comprising disposing a protective layer over the identified good lasers to protect the identified good lasers during the removal step. **Claim 27** Individually inspecting includes individually inspecting each of the lasers to identify whether the lasers being inspected are good lasers or bad lasers, the laser array including a plurality of identified good lasers and a plurality of identified bad lasers, and the removing includes removing at least a portion of each of the identified bad lasers. The method according to claim 23. **Claim 28** Electrically connecting includes electrically connecting the source to each of the identified good lasers and electrically isolating each of the identified bad lasers. The method according to claim 27.

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