# US 8,541,803 B2 · Cadmium-free re-emitting semiconductor construction > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,541,803 B2 - Document ID: US8541803B2 - Status: Granted - Kind: B2 - Application number: 13/379,858 - Filed: 2010-06-25 - Published: 2012-04-26 - Granted: 2013-09-24 - Earliest claimed: 2009-05-05 - Assignees: 3M Innovative Properties Company - Applicants: Terry L. Smith; Michael A. Haase; Thomas J. Miller; Xiaoguang Sun - Inventors: Terry L. Smith; Michael A. Haase; Thomas J. Miller; Xiaoguang Sun - Web page: https://patentgrep.com/patent/US8541803B2 ## CPC - H10H 20/813: having a plurality of light-emitting regions, e.g. multi-junction LEDs or light-emitting devices having photoluminescent regions within the bodies - H10H 20/822: Materials of the light-emitting regions - H10H 20/8512: {Wavelength conversion materials} - H10H: INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS ## Abstract Disclosed re-emitting semiconductor constructions (RSCs) may provide full-color RGB or white-light emitting devices that are free of cadmium. Some embodiments may include a potential well that comprises a III-V semiconductor and that converts light of a first photon energy to light of a smaller photon energy, and a window that comprises a II-VI semiconductor having a band gap energy greater than the first photon energy. Some embodiments may include a potential well that converts light having a first photon energy to light having a smaller photon energy and that comprises a II-VI semiconductor that is substantially Cd-free. Some embodiments may include a potential well that comprises a first III-V semiconductor and that converts light having a first photon energy to light having a smaller photon energy, and a window that comprises a second III-V semiconductor and that has a band gap energy greater than the first photon energy. ## Claims ### Claim 1 A semiconductor construction, comprising: a first potential well for converting light having a first photon energy to light having a smaller second photon energy, the first potential well comprising a first III-V semiconductor; and a window having a band gap energy greater than the first photon energy, the window comprising a first II-VI semiconductor; wherein the window is substantially Cd-free. ### Claim 2 (depends on 1) The construction of claim 1, wherein the first potential well is pseudomorphic. ### Claim 3 (depends on 1) The construction of claim 1, wherein the semiconductor construction is compliant with the RoHS Directive. ### Claim 4 (depends on 1) The construction of claim 1, wherein the light having the first photon energy comprises UV, violet, blue, and/or green light, and the light having the second photon energy comprises red light. ### Claim 5 (depends on 1) The construction of claim 1, wherein the construction is pseudomorphic and disposed on a substrate comprising a second III-V semiconductor, and wherein the second III-V semiconductor comprises GaAs. ### Claim 6 (depends on 1) The construction of claim 1, wherein the first II-VI semiconductor comprises BeMgZnSe or BeZnSe. ### Claim 7 (depends on 1) The construction of claim 1, wherein the first II-VI semiconductor comprises MgZnSSe or BeZnSSe. ### Claim 8 (depends on 1) The construction of claim 1, wherein the first potential well is a component of a stack of pseudomorphic semiconductor layers including one or more absorber layers and optionally one or more additional potential wells, and wherein the stack of semiconductor layers is substantially Cd-free. ### Claim 9 (depends on 1) A light emitting system, comprising: the construction of claim 1 disposed on a light source adapted to emit light having the first photon energy; and a second potential well for converting light having the first photon energy to light having a third photon energy smaller than the first photon energy and greater than the second photon energy, the second potential well comprising a second II-VI semiconductor. ### Claim 10 (depends on 9) The system of claim 9, wherein the second potential well is substantially Cd-free. ### Claim 11 (depends on 9) The system of claim 9, wherein the second potential well is a component of a stack of pseudomorphic semiconductor layers including one or more absorber layers and optionally one or more additional potential wells, and wherein the stack of semiconductor layers as a whole is substantially Cd-free. ### Claim 12 (depends on 9) The system of claim 9, wherein the second II-VI semiconductor comprises MgZnSeTe, ZnSeTe, BeMgZnSe or MgZnSSe. ### Claim 13 (depends on 1) A light emitting system, comprising: the construction of claim 1; a light source adapted to emit light having a third photon energy greater than the first photon energy; and a second potential well for converting the light having the third photon energy to the light having the first photon energy, the second potential well comprising a second II-VI semiconductor. ### Claim 14 (depends on 13) The system of claim 13, wherein the second potential well is substantially Cd-free. ### Claim 15 (depends on 14) The system of claim 14, wherein the second II-VI semiconductor comprises MgZnSeTe, ZnSeTe, BeMgZnSe or MgZnSSe. ### Claim 16 (depends on 13) The system of claim 13, wherein the second potential well is a component of a stack of pseudomorphic semiconductor layers including one or more absorber layers and optionally one or more additional potential wells, and wherein the stack of semiconductor layers as a whole is substantially Cd-free. ### Claim 17 (depends on 13) The system of claim 13, wherein the light having the third photon energy comprises UV, violet, and/or blue light, the light having the first photon energy comprises green light, and the light having the second photon energy comprises red light. ### Claim 18 (depends on 1, 13) The system of claim 13, wherein the second potential well is disposed between the light source and the construction of claim 1.